True$/$False EACH WORTH $2$ POINTS, $10$ pts in Total$)$ T$1)$ True or False: The boundary can neither contain any mass nor occupy any volume in space. T$2)$ True or False: Actual heat engines cannot have a thermal efficiency of $100\%$ but ideal heat engines can. T$3)$ True or False: The back work ratio of a gas$-$turbine cycle increases as a result of intercooling and reheating. T$4)$ True or False: The specific heat at constant volume is a measure of the variation of enthalpy of a substance with temperature. T$5)$ True or False: A resistance heater with an efficiency of $100\%($supplying as much heat as the electricity it consumes$)$ is a violation of the second law of thermodynamics.