Question

It isn't possible to transfer heat from an object at a lower temperature to another object at a _ temperature unless work is done

Answer 1

Heat transfers from high to low. So to complete the statement;

It isn't possible to transfer heat from an object at a lower temperature to another object at a HIGHER temperature unless work is done

Answer 2

Higher. Because this type of heat transfer is conduction, meaning that heat always transfers to cooler objects.