What must be true about two objects if heat is flowing between them? the objects must be different temperatures. the objects must be the same temperature. the objects must both be over room temperature. the objects must both be under room temperature.

Heat always flows from high temperature to low temperature and flows until the temperature between the two locations become equal. hence for the two objects having heat flowing between them, the temperature must be different. one object must have higher temperature than the other object.

hence the correct choice is

the objects must be different temperatures

the answer is b ) square root of 5