Which of these is a chemical change? a. freezing water b. dissolving sugar in water c. tearing up a piece of paper d. lighting a match

Which best explains how a heat pump can heat a room? cold air from the house is moved through pipes, where it absorbs thermal energy. warm air from outside is pushed into the house to replace the cold air. combustion warms the air when chemical energy is transferred to thermal energy. fuel is used to move a piston, which pushes warm air into the house.

Speed is the ratio of the distance of an object moves to

Ecology can best be described as the study of what