Astyrofoam box has a surface area of 0.73 m and a wall thickness of 2.0 cm. the temperature of the inner surface is 5.0°c, and the outside temperature is 25°c. if it takes 8.4 h for 5.0 kg of ice to melt in the container, determine the thermal conductivity of the styrofoam w/m-k

Refrigerant-134a flows through a carnot heat pump cycle at 0.5 kg/s. it is known that the maximum absolute temperature in the cycle is 1.1 times the minimum absolute temperature, and the net power input to the cycle is 2.5 kw. if the refrigerant changes from a saturated vapor to a saturated liquid during the heat rejection process, determine the maximum magnitude of the enthalpy of vaporization for this process in kj/kg (with 3 significant figures).