Which of the following experiments best describes an investigation that measures the effect temperature has on the volume
of a gas?
A. Measure the volume of a balloon filled with room temperature air. Place the balloon in a freezer for an hour and then measure its
volume again.
B. Stretch a balloon over the top of a beaker filled with baking soda and vinegar and observe how the balloon changes volume.
C. Inflate one balloon to a large volume and another balloon to a small volume. Measure the temperature of the air released from
both balloons.
O
D. Measure the pressure of the air in a tire on a cold day, a warm day, and a hot day.

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.