In literature, what is a subject?

If a refrigerator is a heat pump that follows the first law of thermodynamics, how much heat was removed from food inside of the refrigerator if it released 380j of energy to the room?

If gases like carbon dioxide and methane make up less than 1% of the total atmosphere, why is it important for scientists to monitor changes in percentages of these gases?

(01.02 mc) nicole pushes her bike up a hill. overhead, the sun exerts a gravitational force on earth. which statement is true about the bike and earth? they both experience contact forces. they both experience non-contact forces. the bike experiences a non-contact force and earth experiences a contact force. the bike experiences a contact force and earth experiences a non-contact force. they both experience non-contact forces.