When a lump of uranium is broken into smaller pieces, the total surface area of the lump
a. dreases
b. remais the same
c. increases

option C

Explanation:

When the lump of the uranium is broken into small pieces the total surface area of the lump will increase.

When uranium breaks into small pieces number of the surface of uranium increases.  

Increased in the number of the surface will increase the surface area of the broken pieces of the Uranium.

so, the correct answer is option C

be subject to a force andchange its motion

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.