An 84kg refrigerator is located on the 70th floor of a skyscraper (320 above ground ). Calculate the potential energy 

Which explanation describes the forces involved for a person to walk down the sidewalk? a. the person's feet push backward on the sidewalk; the sidewalk pushes backward on the person. b. the person's feet push forward on the sidewalk; the sidewalk does not push on the person. c. the person's feet push backward on the sidewalk; the sidewalk pushes forward on the person. d. the person's feet push forward on the sidewalk; the sidewalk pushes forward on the person.

When an object is heated it contracts. a. true b. false

Sort the images based on whether there's a force of attraction or repulsion between the magnets shown. attraction repulsion