[3) Calculate the force (in N) the woman in the figure below exerts to do a pusnrup at (onstant speed, taking all data to be known to three digits. (You may heed to use torque methods from a later chapter.) m=56kg (b) How much work (in J) does she do if her center of mass rises 0.280 m? :l1 (c) What iS her useful power output (in W) if she does 24 pusheups in 1 min? (Should work done lowering her body be included? See the discussion of useful work in Work, Energy. and Power in Humans.) :IW