(a) Calculate the force [in N) the woman in the gure below exerts to do a push-up at constant speed, taking all data to be known to three digits. (You may need to use torque methods from a later chapter.) m=68kg (b) How much work (in J) does she do if her center of mass rises 0.200 rn?I |:|J (c) What is her useful power output [in W] if she does 21 push-ups in l min? [Should work clone lowering her bodyr be included? See the discussion of useful work in Work, Energy, and Power in Humans.) :W