Which statement about friction in a system is true?(1 point) A. Friction converts some energy on the molecular scale to energy on the macroscopic scale.

B. Friction increases the total energy of a system.

C. Friction converts some energy on the macroscopic scale to energy on the molecular scale.

D. Friction decreases the total energy of a system.

Because air contracts as it cools, the air pressure inside a freezer is typically lower than on the outside. why do ice cubes inside a freezer tend to shrink over time? a. the ice dissolves oxygen from the air, forming a denser crystalline matrix.b. the ice reacts chemically with carbon dioxide in the air, forming gaseous carbon compounds.c. the ice melts, and then the liquid freezes as ice crystals on the bottom of the freezer.d. the ice sublimes, and then the water vapor deposits as ice crystals on the sides of the freezer.

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.

Acar travels in reverse. it covers 150 meters in 12 seconds what is the velocity of the car what is the speed of the car