Consider equal volumes (say 1 l) of a given substance in the solid, liquid, and gas phases. arrange them in order of decreasing mass based on the trend for the average substance. if the mass difference between samples is relatively small (10% or less), rank the items as equivalent. rank from greatest to least mass. to rank items as equivalent, overlap them.

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.

if the person is shown to have +90n, then ans is -10n.

if the person is shown to have -90n, then ans is +10n.

3. dark matter

empty space could also be a simple vacuum