Help pls it’s timed

During an investigation of an xss attack, the investigator comes across the term "[a-za-z0-9\%]+" in analyzed evidence details. what is the expression used for?

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.

Aboy jumps into a cold swimming pool and his body tempature goes down hus muscles ,blood vessels