Answer:
Option A
Explanation:
From the question we are told that:
Mass 
Velocity 
Generally the equation for momentum for Ball A is mathematically given by
Initial Momentum



Final Momentum

Therefore

Generally the equation for momentum for Ball B is mathematically given by
Initial Momentum



Final Momentum

Therefore

Option A
Answer:
B. changing by a constant amount each second
Explanation:
thats my answer
If a red blood cell is 7 x
m in size, it means that such a cell is 7 microns or micrometer in size. The unit that completes the sentence will, thus, be microns or micrometer.
According to international system of measurement:
m = decimeter
m = centimeter
m = millimeter
m = micrometer or micron
m = nanometer
Thus, a measurement of 7 x
m is the same is 7 micons or 7 micrometer.
More on metric conversion can be found here: brainly.com/question/17767575
1) 29.4 N
The force of gravity between two objects is given by:

where
G is the gravitational constant
M and m are the masses of the two objects
r is the separation between the centres of mass of the two objects
In this problem, we have
(mass of the Earth)
(mass of the box)
(Earth's radius, which is also the distance between the centres of mass of the two objects, since the box is located at Earth's surface)
Substituting into the equation, we find F:

2) 
Let's now calculate the ratio F/m. We have:
F = 29.4 N
m = 3.0 kg
Subsituting, we find

This is called acceleration of gravity, and it is the acceleration at which every object falls near the Earth's surface. It is indicated with the symbol
.
We can prove that this is the acceleration of the object: in fact, according to Newton's second law,

where a is the acceleration of the object. Re-arranging,

which is exactly equal to the quantity we have calculated above.
Answer:
2156 J
Explanation:
From the question,
Work done = Combined mass of the bucket and water×height×gravity.
W = (M+m)hg............................. Equation 1
Where M = mass of water, m = mass of the bucket, h = height, g = acceleration due to gravity.
Given: M = 20 kg, m = 2 kg, h = 10 m
Constant: g = 9.8 m/s²
Substitute these value into equation 1
W = (20+2)×10×9.8
W = 22×98
W = 2156 J