Gas always expands or contracts to exactly fill whatever you put it in.
So to measure the volume of a gas, just measure the volume of the jar, the tank, the bottle, the can, or the balloon that the gas is in.
Your answer would be D- Knowledge of the environment.
I hope this helped... ;)
It's B inertia if I remember correctly you can also rule out A,S and D so...
Because maybe the ball was going downwards or he was getting ready to catch the ball. one of those 2.
In a vacuum, all objects fall at the same rate. Meaning that the 100 kg ball will fall at the same speed as the 10 kg ball. Assuming that both objects share the same starting acceleration, they will keep that acceleration until the fall is stopped.
In other words, your answer is the first one, Both objects will accelerate at 9.8 m/s