Acar engine has a power output of 65 hp. if the fuel consumption rate of the car is 45 lbm/hr and the fuel has a heating value of 19,000 btu/lbm (that is 19,000 btu of energy is released for each lbm of fuel burned), determine the thermal efficiency of the engine. [note: 1hp=2544 btu/hr]

Asolid cylinder is concentric with a straight pipe. the cylinder is 0.5 m long and has an outside diameter of 8 cm. the pipe has an inside diameter of 8.5 cm. the annulus between the cylinder ad the pipe contains stationary oil. the oil has a specific gravity of 0.92 and a kinematic viscosity of 5.57 x 10-4 m2/s. most nearly, what is the force needed to move the cylinder along the pipe at a constant velocity of 1 m/s?