(1 point) The rate at which a machine operator's efficiency, E(t) (expressed as a percentage), changes with respect to time t is given by dE = 32 - 12t dt where t is the number of hours the operator has been at work. (A) Find E(t), given that the operator's efficiency after working 2 hours is 80% that is, E(2) = 80. Operator's efficiency function E(t) = (B) What is the operator's efficiency after 5 hours