Which of the following is not a fossil fuel?
a.
oil
c.
coal
b.
natural gas
d.
hydrogen

If a sphere and a cure have the same mass and are propelled up a ramp with the same force, which would travel father up the ramp? explain.

The pressure proportional to the area a- inversely b- directly c- increase d-decrease

Ahot-air balloon takes off from the ground traveling vertically with a constant upward acceleration of magnitude g/4. after time interval δt, a crew member releases a ballast sandbag from the basket attached to the balloon. how many seconds does it take the sandbag to reach the ground? (express your answer in terms of δt)