HELP PLEASE! I'M FAILING THIS CLASS! A ramp is used to load furniture onto a moving truck. The person does 1341 J of work pushing the furniture up the ramp, and the ramp does 765 J of work. Calculate the efficiency of the ramp.

Yvette hangs a 2.4kg bird feeder in the middle of a rope tied between two trees. the feeder creates a tension of 480 n in each side of the the rope.

Assume that a person skiing high in the mountains at an altitude of h = 15100 ft takes in the same volume of air with each breath as she does while walking at sea level. determine the ratio of the mass of oxygen inhaled for each breath at this high altitude compared to that at sea level. assume that the air composition (i. e. % of air that is oxygen) is the same at sea level as it is at 15100 ft.

What is the single most important equation in all of physics?