Which variables did the student need to control in this investigation? Select all that apply. 1. the mass of the balls 2. the diameter of the balls 3. the height from which the balls were dropped 4. the material in the pan !I Need This Done Fast!

Agas is contained in a vertical, frictionless piston–cylinder device. the piston has a mass of 3.2 kg and a cross-sectional area of 35 cm2. a compressed spring above the piston exerts a force of 190 n on the piston. if the atmospheric pressure is 95 kpa, determine the pressure inside the cylinder.

Positrons are spontaneously emitted from the nuclei of

Astudent pushes a 60-n block across the floor for a distance of 10 m. how much work was done to move the block