Which of these items are made of cells? Check all that apply.

air

bacteria

horses

humans

mushrooms

rocks

water

When you push downward on a book at rest on a table, you feel an upward force. does this force depend on friction? defend your answer.

A250-n box is at rest on a frictionless horizotal floor. then a person shoves the box with a non-zero force of magnitude p. which statement best describes the relationship betweeen p and the motion of the box after it was shoved? -the box will not move when p< 250n but otherwise will accelerate at a constant rate that is directly proportional to p - the box will begin moving at a speed that is directly proportional to p, then will gradually slow to a halt -the box will move with constant velocity at a speed that is directly proportional to p -box will accelerate across the floor at a constant rate that is directly proportional to p

Which accurately compares concave and convex lenses?