Penny is observing a substance that is experiencing a change of state. In its first state, the particles in the substance are close together, but able to move around one another. After the change, the particles are no longer close together. Which change of state has occurred? Group of answer choices sublimation melting condensation evaporation

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.

Photosynthesis uses co2 and cellular respiration produces co2. we call the point when the two processes are in balance--when there is no net production of co2--the compensation point. how might you limit one of the processes in order to achieve a compensation point?

Which statement is a physical property? becomes moldy quicklyeasy to digestconducts electricity poorlydoes not burn