what units is length in

Answers

Answer 1
Some units of length are: meters, centimeters, kilometers, etc...
Answer 2
Sisteme International recognises only meters.
In physics calculations we use only meters.

However, there are also multimeters, kilometres, ft, miles

Related Questions

T/F:Most of the energy we use today comes from renewable sources.

Answers

I'm not very sure but I think it is true.

what two kinds of motion combine to to produce projectile motion

Answers

Horizontal and Vertical.

Galileo discovered that the orbits in which planets move around the Sun are elliptical.

True or False

Answers

Galileo discovered that the orbits in which planets move around the Sun are elliptical.

false

Answer: False

Explanation:

Galileo proved the heliocentric model by studying the position of Venus. He believed the sun to be center and all other bodies revolved around it in circular orbits which was disproved by Kepler. Kepler developed laws of planetary motion. One of which states that planets revolve around Sun in elliptical orbits with Sun at one of its foci. Thus, the given statement is false.

An object is dropped from a 400-ft tower.

a) when does it hit the ground?

b) how fast is it going at the time of impact?

Answers

we know that k = 400 

vt = -32t ;  dt = 400 - 16t^2

0 = 400 - 16t^2

when it hit the ground

0 = 400 - 16t^2

t = +/- 5s

so , 
a = 5 s
b = 160 ft/s

Hope this helps

So,a)It will hit ground at 4.52seconds.b)At 145 ft/s fast is it going at the time of impact

An object is dropped from a 400-ft tower:

a) When does it hit the ground? Using the formula: time = [tex]\sqrt[1]{2*height/g}[/tex], where g is the acceleration due to gravity (32 ft/s²), the time taken to hit the ground is approximately 4.52 seconds.

b) How fast is it going at the time of impact? The velocity of the object when it hits the ground can be calculated as velocity = g * time, which gives a velocity of about 145 ft/s.

Which of the following best defines volume?
A. The amount of matter in a substance.
B. The shape of a sample of matter.
C. The amount of space that a sample of matter takes up.
D. The way that a substances atoms are arranged Which of the following best defines volume?
A. The amount of matter in a substance.
B. The shape of a sample of matter.
C. The amount of space that a sample of matter takes up.
D. The way that a substances atoms are arranged

Answers

Answer:

C. The amount of space that a sample of matter takes up.

Explanation:

Volume is defined as the 3 dimension shape which is enclosed by a closed surface. It is defined that the space which is occupied by the substance.

The volume is defined in the cubic units.

The volume of container generally is the classification of the amount of space which the substance hold rather than the space which is displaced by the container itself.

Final answer:

Volume is the amount of space that a sample of matter takes up.

Explanation:

Volume is best defined as the amount of space that a sample of matter takes up. It is a measure of how much space an object occupies. Volume can be expressed in different units such as cubic meters, liters, or milliliters.

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A brass washer has an outside diameter of 4.50 cm with a hole of diameter 1.25 cm and is 1.50 mm thick. The density of brass is 8599 kg/m3. If you put this washer on a laboratory balance, what will it "weigh" in grams?

Answers

Final answer:

The weight of the brass washer is 82.3 grams.

Explanation:

The weight of the brass washer can be calculated using its density and volume. The volume of the washer can be found by subtracting the volume of the hole from the volume of the outer cylinder. The formula for the volume of a cylinder is πr^2h, where r is the radius and h is the height.

Given that the outside diameter is 4.50 cm, the radius is half of that, which is 2.25 cm (or 0.0225 m). The height of the washer is 1.50 mm, which is 0.0015 m. Using these values, we can calculate the volume of the washer:

Volume = π(0.0225)^2(0.0015) = 9.5747 x 10^-6 m^3

Now, we can calculate the weight of the washer using its volume and density:

Weight = Volume x Density = 9.5747 x 10^-6 m^3 x 8599 kg/m^3 = 82.3 g

Final answer:

The weight of the brass washer on a laboratory balance would be 59.5 grams.

Explanation:

To find the weight of the brass washer, we need to calculate its volume and then multiply it by the density of brass. The volume of the washer can be found by subtracting the volume of the hole from the volume of the outside part of the washer.

The volume of the outside part of the washer can be calculated using the formula for the volume of a cylinder: V = π[tex]r^2[/tex]h. In this case, the radius (r) is half the outside diameter, so r = 4.50 cm / 2 = 2.25 cm = 0.0225 m. The height (h) is the thickness of the washer, which is 1.50 mm = 0.0015 m. Plugging these values into the formula gives us V = π(0.0225 [tex]m^2[/tex](0.0015 m) = 7.21 x [tex]10^{-6}[/tex] [tex]m^3[/tex].

The volume of the hole can also be found using the formula for the volume of a cylinder, since it is cylindrical in shape. The radius (r) of the hole is half the hole diameter, so r = 1.25 cm / 2 = 0.0125 m. The height (h) of the hole is the same as the thickness of the washer, which is 0.0015 m. Plugging these values into the formula gives us V = π(0.0125 [tex]m^2[/tex](0.0015 m) = 2.94 x [tex]10^{-7}[/tex] [tex]m^3[/tex].

Now, we can find the volume of the washer by subtracting the volume of the hole from the volume of the outside part: V_washer = 7.21 x [tex]10^{-6} m^3[/tex] - 2.94 x [tex]10^{-7} m^3[/tex] = 6.92 x [tex]10^{-6} m^3[/tex].

Finally, we can calculate the weight of the washer using the formula W = V_washer * density. Plugging in the values gives us W = 6.92 x [tex]10^{-6} m^3[/tex] * 8599 kg/[tex]m^3[/tex] = 5.95 x [tex]10^{-2}[/tex] kg = 59.5 g.

J is the midpoint of The coordinates of J are (-8,7) and the coordinates of K are (3,4) find the coordinates of L. can someone help me? i get really confused with geometry and im trying to finish this final and im not sure how to solve this problem ...?

Answers

Solution:

STEP 1:Let the coordinates of L be (x,y). Then use the Midpoint formula to solve for x and y 
(3 + x)/2 = -8 and (4+ y)/2 = 4 

3 + x = -16 and 4 + y =8
x = -16 -3 and y = 8 - 4
x= -19 and y= 4 

Therefore the coordinates of L are (-19,4)

I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!

Particle A and particle B are held together with a compressed spring between them. When they are released, the spring pushes them apart, and they then fly off in opposite directions, free of the spring. The mass of A is 2.00 times the mass of B, and the energy stored in the spring was 68 J. Assume that the spring has negligible mass and that all its stored energy is transferred to the particles. Once that transfer is complete, what are the kinetic energies of each particle?

Answers

I have a solution to the same problem here, however, with a slight change in the given such as: 2 times; 68 Joules. When examining this solution, I can assure you that you can now answer the problem on your own.

Using the conservation of momentum, 

0 = MaVa + MbVb 

where 

Ma = mass of particle A 

Va = final velocity of particle A 

Mb = mass of particle B 

Vb = final velocity of particle B 

Since Ma = 4(Mb), then the above formula becomes 

0 = 4(Mb)(Va) + Mb(Vb) 

Va = - (Vb/4) 

(KE)a = kinetic energy of particle A = (1/2)(Ma)(Va)^2 

(KE)b = kinetic energy of particle B = (1/2)(Mb)(Vb)^2 

Taking the ratio of the two kinetic energies, 

(KE)b/(KE)a = [(1/2)(Mb)(Vb)^2]/[(1/2)(Ma)(Va)^2] 

and since 

Ma = 4(Mb) 

and 

Va = -Vb/4 

then the above simplifies to 

(KE)b/(KE)a = [(Mb)(Vb)^2]/[(4Mb)(Vb/4)^2] 

(KE)b/(KE)a = 1/(4*1/16) = 4 

Therefore, 

(KE)b = 4(KE)a -- call this Equation A 

Using the law of conservation of energy, 

58 = (KE)a + (KE)b 

and since (KE)b = 4(KE)a (from Equation A), the above simplifies to 

58 = (KE)a + 4(KE)a 

5(KE)a = 58 

(KE)a = 11.6 joules 

Hence, 

(KE)b = 4(11.6) = 46.4 joules 

ANSWER: 

Kinetic energy of particle A = 11.6 joules 

Kinetic energy of particle B = 46.4 joules 

Hope this helps.

Which best describes the difference between internal and thermal energy?

Answers

Internal energy cannot be transferred whereas, thermal energy is the energy due to temperature difference

Internal energy is the total potential and kinetic energies in a substance, and thermal energy is the part of internal energy that can be transferred to another substance. The answer on edge would be C.

An archer pulls back the string of a bow to release an arrow at a target. Which kind of potential energy is transformed to cause the motion of the arrow?

Answers

The correct answer should be elastic.

Answer: elastic potential energy

Explanation:

The form of energy stored in the string of the bow is elastic potential energy. Elastic potential energy is the energy stored in an elastic object (such as the string of a bow) when the object is compressed/stretched by a certain amount x with respect to its natural length. The elastic potential energy stored in the object is given by

[tex]U=\frac{1}{2}kx^2[/tex]

where k is the spring constant of the elastic string, and x is the compression/stretching.

Which of the rays drawn above would be correct as the light goes from the air into the water?

A, B, or C ??

Answers

The correct answer you are looking for is "A". Have a great day!

Answer:a

Explanation:test

Can someone please help me how to set this up?

A police car receives a radio call to catch a vehicle which is speeding down the highway at 80 mph. The police car, which is 12 miles away, drives after it at 108 mph. How long will it take for the police car to catch up? ...?

Answers

The car has a 12 mile head start, going 80 mph, so his distance is:dcar=80∗t+12
The is going at 108 mph, so his distance is:dcop=108t
Setting them equal to each other we get:80t+12=108t⇒12=28t⇒t=1228=37
So 3/7 of an hour.about 25.7 mins.

Answer:

The time is 0.428 hr.

Explanation:

Given that,

Final speed = 108 mph

Initial speed = 80 mph

Distance = 12 miles

We need to calculate the time

Using formula of time

[tex]v = \dfrac{d}{t}[/tex]

d = distance

t = time

Put the value into the formula

[tex]108-80=\dfrac{12}{t}[/tex]

[tex]t = \dfrac{12}{108-80}[/tex]

[tex]t =0.428\ hr[/tex]

Hence, The time is 0.428 hr.

Fill in the blank:energy can never be created or destroyed, just ------- or --------

Answers

I am pretty sure the answer is transformed or converted.

The efficiency of a screw is low because of _____.



width

friction

length

height

Answers

The correct answer that would best complete the given statement above would be the second option. A screw is an inclined plane wrapped around a cylinder. The efficiency of a screw is low because there is more input than output. In other words, it is because of friction. Hope this answer helps.

Answer:

The efficiency of a screw is low because of friction.

Explanation:

A screw is a simple machine that is used to convert a torque to linear force and rotational motion to linear motion. The efficiency of a screw is given by :

[tex]\eta=\dfrac{Fl}{2\pi T}[/tex]

Where

l = pitch distance in mm

T = torque in N-m

The efficiency of screw is less because the output is less as compared to input or there is more input than output. This implies that there is more friction.

Hence, the correct option is (b) "friction".

When an electric current passes through water, _____ takes place, breaking down the compound into hydrogen and oxygen.?

Answers

I believe that would be electrolysis.

What is the sequence of energy transformations associated with a hydroelectric dam?

Answers

gravitational potential energy to kinetic energy into mechanical then electrical 
To make it simple, the right answer is B.

The theory of plate tectonics developed in part from an earlier hypothesis about how continents move. What is the name of this earlier hypothesis?

A.
continental drift
B.
earthquake development
C.
natural selection
D.
evolution


Answers

I think it maybe A. Continental Drift

its A i know my science

The gravitational force between a satellite and Earth’s moon is 324 N. The mass of the moon is 7.3 × 1022 kg. If the distance from the moon to the satellite is 2.6 × 106 m, what is the mass of the satellite?

Answers

Answer:

449.824 kg

Explanation:

F = Gm₁m₂/r²

Above equation can be used to find the gravitational force between two objects.

Here F is the Gravitational force. m₁ , m₂ are the masses of the objects and r is the distance between the objects. Let's take m₁ as the mass of the moon. Then m₂ is the mass of the satellite.

We are given that F = 324 N , m₁ = 7.3 * 10²²kg and r = 2.6 * 10 ⁶m.

              324  =  6.67×10⁻¹¹ × m₁ × 7.3×10²² / (2.6 × 10⁶)²

                  m₁ = 449.824 kg

Answer:

answer above is right just round its 450kg

Explanation:

Which of the following is not a mineral?

A. Natural diamond
B. Coal
C. Gold

Answers

Coal. Coal comes front plant matter so it isn't a true mineral technically
Both of the diamond and gold are minerals , coal has some combinations of minerals but is classified as a sedimentary rock. So therefore B. coal is not a mineral


Which statements about Earth’s core help explain Earth’s magnetic field? Check all that apply.



Earth’s core is composed of magnets.


The inner core is solid.


The outer core is solid.


The inner core is liquid and moving.


The outer core is liquid and moving.


Earth’s core is composed of iron and nickel.

Answers

The inner core is liquid and moving.

Answer:

The inner core is solid.

The outer core is liquid and moving.

Earth’s core is composed of iron and nickel.

Explanation:

Convection currents are produced in the outer liquid core. This motion together with the Earth's rotation creates a system of electrical currents, since it is composed of metals such as iron and nickel. The magnetic fields generated by the electric currents align, creating the Earth's magnetic field. The solid inner core acts as a stabilizer of the magnetic field generated by the liquid outer core.

A hydraulic press for compacting powdered samples has a large cylinder which is 10.0 cm in diameter, and a small cylinder with a diameter of 2.0 cm. A lever is attached to the small cylinder as shown in The sample, which is placed on the large cylinder, has an area of 4.0 cm2.
What is the pressure on the sample if F = 270 N is applied to the lever?

Answers


F small cylinder = 2.F
2.F/s = p = (F sample/S)
p sample = F sample/S sample
▬▬▬
> p sample = 2.F.S/s/S sample = 2.F.(D/d)²/S sample
> p sample = 2*280*(10/2)^2/4E-4 = 3,50E+07 u.S.I.
> p sample = 35,0 MPa = 345 atm

The hydraulic pressure on sample is [tex]3.35*10^{7} N/m^{2}[/tex].

What is hydraulic pressure?

Hydraulic pressure is the force imparted per unit area of a liquid on the surfaces which it has contact.

The magnitude of force acting on the small cylinder is equal to [tex]F_{N}[/tex].

In static equilibrium, all the torques should add up to zero:[tex]F_{N}l - 270(2l)= 0\\F_{N} = 270(2)\\F_{N} = 540 N[/tex]

The pressure applied to the fluid (through the small cylinder):

[tex]P= \frac{540}{\pi (\frac{2*10^{-2} }{2} )^2}[/tex]

[tex]P = 1.71*10^{6} Pa[/tex]

The force of fluid on the large cylinder:

[tex]F= P\pi R^{3} \\F= 1.71*10^{6} \pi (0.05^{2} )\\F= 1.34*10^{4} N[/tex]

The pressure on the sample:

[tex]P_{S} =\frac{F}{A} \\P_{S}= \frac{1.34*10^{4} }{4*10^{-4} } \\P_{S}= 3.35*10^{7} N/m^{2}[/tex]

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A 70kg divers steps off of a 10m tower and drops from rest straight into the water. If he comes to rest 5m beneath the surface, determine the average resistance force exerted on him by the water.

Answers

Kinetic Energy:
K E= m g h
h = 10 m,  d = 5 m.
m g ( h + d ) - F d = 0
m g ( h + d ) = F d
70 * 9.8 * 15 = F * 5
10,290 = 5 F
F = 10,290 : 5
F = 2,058 N

First, we need to calculate the total distance that the diver travelled. The diver jumped off a 10-meter tower and went 5 meters under the water. Therefore, the total distance travelled by the diver is 10 meters (from the tower) plus 5 meters (underwater), which equals 15 meters.

Next, we will determine the work done on the diver. The work done is equal to the change in potential energy, which can be calculated by multiplying the diver's mass by gravity and then by the total distance the diver travelled. Given that the diver's mass is 70kg and the acceleration due to gravity is 9.8m/s², the work done is 70kg * 9.8m/s² * 15m, which equals 10290 Joules.

Finally, we'll find the average resistance force exerted on the diver by the water. The work done on the diver is also equal to the average force times the distance. Therefore, the average force is the work done divided by the distance. When you divide the work done (10290 Joules) by the total distance travelled (15 meters), you get an average force of 686 Newtons.

Hence, the total distance travelled by the diver in water is 5 meters, the work done on the diver is 10290 Joules, and the average resistance force exerted on the diver by the water is 2058 Newtons.

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you did 150 joules of work lifting a 120 -N backpack.
how high did you lift the backpack?
how much did the backpack weigh in pounds

Answers

you did 150.j of work lifting a 120.N back

The backpack was lifted 1.25 meters high, and it weighed approximately 26.977 pounds.

To determine how high you lifted the backpack, we can use the formula for work done against gravity, which is W = F × h, where W is work (in joules), F is force (in newtons), and h is height (in meters). Since you did 150 joules of work to lift a 120-N backpack, we can rearrange the formula to solve for height (h): h = W / F = 150 J / 120 N = 1.25 meters. You lifted the backpack 1.25 meters high.

To find out how much the backpack weighed in pounds, we use the conversion factor that 1 newton is approximately equal to 0.224809 pounds. Therefore, 120 N × 0.224809 lb/N = 26.977 pounds. The backpack weighed approximately 26.977 pounds.

The following graph shows the rates of decay for four parent isotopes. Based on the graph, which parent isotope most likely has a half-life of 13 billion years?

A

B

C

D

Answers


Just look at the graph, and find a curve that has fallen to
half of its original value 95 = 47.5 in 13 B years.

Do I really hafta tell you which one it is ?

















It's curve ' C ' .

Answer:

A or B (mostly A)

Explanation:

After 14 billion years, approximately 85% of the original parent isotope will still exist, compared to roughly 45% of parent isotope C, 12.5% of parent isotope B, and nearly none of the parent isotope A!

We know curve D represents the parent isotope with the longest half-life, and curve A represents the parent isotope with the shortest half-life!

We also know it cannot be D or C. So we are stuck with curves B and A! However, since parent isotope B has 12.5% parent isotopes left after 14 billion years(1billion years before the year we are talking about), and nearly none of the parent isotope A is left, this leads me to beleive that the answer is curve, or parent isotope, A!

I am sorry if i am wrong though.

Have a marvelous day!

A 65kg person throw a 0.045kg snowball forward with a ground speed of 30m/s. A second person, with a mass of 60kg, catches the snowball. Both people on the skate. the first person is initially moving forward with speed of 2.5m/s, and the second person is initially at rest. what are the volocities of the two people after the snowball is exchanged? disregard friction between the skates and the ice

Answers

Well, st first we should find initial momentum for the first person represented in the task which definitely must be :
[tex](65+0.045)*2.5[/tex]
And then we find the final one :  [tex]65*x + 0.045*30[/tex]
Then equate them together : [tex]x=2.48 m/s[/tex] 
So we can get the velocity, which is [tex] is 2.48 m/s[/tex]
In that way, according to the main rules of conservation of momentum you can easily find the solution for the second person.
Regards!

Suppose that two objects attract each other with a gravitational force of 16 units. If the distance between the two objects is doubled, what is the new force if attraction between the two objects?

Answers

The formula for the gravitational force has (distance)² in the denominator.
That tells us that more distance produces less force, and that the force
shrinks as fast as the square of the distance grows.

Double the distance  ==> 1/(2)² as much force = 1/4 the force = 4 units

Answer:

4

Explanation:

a moving truck has more __ energy than a parked truck

Answers

Final answer:

A moving truck has more kinetic energy than a parked truck.

Explanation:

In physics, potential energy is the energy that an object possesses due to its position or condition. When comparing a moving truck and a parked truck, the moving truck has more kinetic energy than the parked truck.

Does gravity increase or decrease with greater distance?

Answers

Decrease. Gravity is stronger here on earth than on the moon.

A force of 400 Newtons stretches a spring 2 meters. A mass of 50 kilograms is attached to the end of the spring and is initially released from the equilibrium position with an upward velocity of 10 m/s. After finding the equation of motion, calculate x(t = pi/12).

Answers

If we start taking into account the free body diagram, we then start damping motion of a body by means of this equation:
m * d^2 x/dt^2 + c* dx/dt + k* x = 0 

free undamped motion is when (c =0) 
therefore 
50* d^2 x/dt^2 + 200* x = 0 
w = omega = sqrt(k/m) = sqrt(200/50) = 2 

Then  

A*cos(w*t) + B*sin(w*t) = x 

find A and B using intial conditions and you will get the rest that you need. Hope this helps

If you wanted to increase the gravitational force between two objects what would you do

Answers

double the force on the object

it would decrease the distance

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What's the difference between the words "morose" and "sullen"? All of the records from yazoo land were bruned in public in grorgia's captial city of atlanta savannah louisville athens 1. Which of the following does not need to be done when constructing a frequency distribution? A) select the number of classes desired B) find the range C) make the class width an even number D) use classes that are mutually exclusive2. What are the boundaries of the class 12-16? A) 11.5 and 16.5 B) 10 and 18 C) 12 and 16 D) 43. Which of the following pairs of class limits would be appropriate for grouping the numbers 12, 15, 10, and 17 ? A) 9-13 and 13-17 B) 10-12 and 15-17 C) 10-12 and 13-17 D) 10-13 and 14-17 1. Which of the following does not need to be done when constructing a frequency distribution? A) select the number of classes desired B) find the range C) make the class width an even number D) use classes that are mutually exclusive2. What are the boundaries of the class 12-16? A) 11.5 and 16.5 B) 10 and 18 C) 12 and 16 D) 43. Which of the following pairs of class limits would be appropriate for grouping the numbers 12, 15, 10, and 17 ? A) 9-13 and 13-17 B) 10-12 and 15-17 C) 10-12 and 13-17 D) 10-13 and 14-17 When you scan newspapers, television and magazines to look for speech topic ideas what are you using?A interest chartsB mind mappingC media promptsD brainstormingi think its C Which approach to psychology did the publication of On Human Nature initiate?A. evolutionary psychologyB. behaviorismC. functionalismD.Gestalt psychology Which of the following sentences could take the place of: El mdico les da unas pastillas a los pacientes. Se las da. Le las da. A community is building a square park with sides that measure 80 meters. To separate the picnic area from the play area, the park is split by a diagonal line from opposite corners. Determine the approximate length of the diagonal line that splits the square. If necessary, round your answer to the nearest meter. ...? solving system using subsitution question a shopper purchased 8 t-shirts and 5 pairs of pants for $220.The next day he purh pair of purchased 5 tshirts and 1 pair of pants for $112.How much does each tshirt and each pair of pants cost? ...? I'M GIVING 20 POINTS!!!! I need two people answering this so I can give Brainliest to the best answered answer. Give me definitions, examples, pictures, and videos if possible of these sports:-Table tennis (Ping Pong)-Juksei-Futsal-Janzi-PesapelloAnswer me good and maybe you will get a Brainliest. BUT..... you need to have everything I asked for The connotation of narrow in the passage creates a feeling ofindifference.monotony.satisfaction.suffocation. plants are classified as Recessive genes are expressed under which of the following conditions?A. Every time they are found in an organism.B. In green plants that reproduce through seeds.C. When asexual organisms produce a pair of offspring.D. Only in the absence of dominant genes for the same trait. A room has 3 lamps. From a collection of 12 light bulbs of which 5 are not working, Richard selects 3 at random and puts them in the sockets. What is the probability that he will have light? ...? Which of the following quotations best explains why Roosevelt believes he was elected? A. "To raise the values of agricultural products." B. "Our greatest primary task is to put people to work." C. "This Nation asks for action, and action now." D. "The clean satisfaction that comes from the stern performance of duty..." When you propose a solution to your argument during the conflict resolution process, you should make sure you are using ______. a. Arguments from emotion b. Ad hominem arguments c. Neutral Arguments d. None of the above In two or more complete sentences explain how to balance the chemical equation, KClO3 KCl + O2 and include all steps. A person can purchase a particular model of a new car with a choice of ten colors, with or without automatic transmission, with or without four-wheel drive, with or without air conditioning, and with two, three, or four radio-CD speakers. How many different options are there for this model of car? Which of the following medicinals are utilized to help reduce pain?A. Tranquilizers B. Analgesics C. Insulin injectables D. Sulfonamides 9g+2=20 please help What Kind Of Noun Is Samples? Steam Workshop Downloader