A 230 kg piano must be lifted onto a stage that is 1.7 m high: a) If the piano is lifted straight up by some very strong people, how much force must they apply? b) How much work have they done? c) If the stage crew only needs to apply a force of 300 N to get the piano onto the stage if they use a 15 m ramp, how much work is done using the ramp? d) What is the efficiency of the ramp? e) You should notice that the force needed to lift the piano in A is larger than the force needed to lift the piano in C. How is it possible that the piano can be raised with much less force when the incline is used? (In other words, what is the "trade-off" of using an inclined ramp?)