Bernard Bernard

05/02/2023 · Escuela secundaria superior

The rate at which a machine operator's efficiency, \( E \) (expressed as a percentage), changes with respect to time \( t \) is given by \( \frac{d E}{d t}=35-12 t \), 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 hr is \( 79 \% \); that is, \( E(2)=79 \). b) Use the answer in part (a) to find the operator's efficiency after 3 hr ; after 5 hr .