What happens during the first step in dna replication?

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.

Need with these questions . need the answers in a rush for these questions are the answers i put down are correct or not? ?

What are levels of ecology and how can we remember them