Answer:
4.536hp
Explanation:
The decrease in the heat gain of the room is determined from difference in electrical inputs:
[tex]Q = W_{shaft} (\frac{1}{n_{1} } - \frac{1}{n_{2} })\\Q = (75hp)*(\frac{1}{0.91 } - \frac{1}{0.963 })\\\\Q = 4.536 hp[/tex]