1.—— can be described as the amount of 'stuff
(matter) in an object.

Standing side by side ,you and a friend step off a bridge at different times and fall for 1.6s to the water below.your friend goes first,and you follow after he has dropped a distance of 2.0m.when your friend hits the water,is the seperation between the two of you 2.0m or more than 2.0m? verify your answer with a calculation.

In the first law of thermodynamics, triangle e=q-w, what does q stand for

If jerome is swinging on a rope and transferring energy from gravitational potential energy to kinetic energy, is being done.