Can someone me with my physics questions? i need correct answers only consider a situation where you are playing air hockey with a friend. the table shoots small streams of air upward to keep the puck afloat and to minimize friction. when you barely tap the puck forward, it a. slows and stops. b. moves with a constant speed until hitting the other end. c. moves backward with an equal and opposite velocity. d. continues to accelerate.

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).