A sled and rider with a combined mass of 70 kg are at the top of a hill that rises 9 m above the level ground below. The sled is given a push, providing an initial kinetic energy at the top of the hill of 1,200 J. a. Choosing a reference level at the bottom of the hill, what is the potential energy of the sled and rider at the top of the hill? sled and rider at the top of the hill? of the sled and rider at the bottom of the hill? b. After the push, what is the total mechanical energy of the hill?c. If friction can be ignored, what will be the kinetic energy of the sled and rider at the bottom of the hill?

Clara is shopping in a grocery store with her friend. each has their own shopping cart in which they want to place their items. the shopping carts are identical. clara and her friend add the same type and number of items to each of their carts. in the baking aisle, however, clara adds 20 pounds of sugar to her own cart, and her friend adds only 10 pounds of sugar to her own cart. which of the following statements best explains what clara must do to accelerate at the same rate as her friend? a. she must add more sugar to her cart. b. she must apply more force to move her cart. c. she must add 20 pounds of salt instead of 20 pounds of sugar to her cart. d. she must apply less force to move her cart.