Explanation
\(\text { Efficiency }=\frac{\text { Power }_{\text {out }}}{\text { Power }_{\text {in }}} \times 100\)
\(E=\frac{P_{o}}{P_{\mathrm{i}}} \times 100\)
So
\(P_{o}=\frac{E \times P_{\mathbf{i}}}{100}\)
\(P_{o}=\frac{E \times P_{\mathrm{i}}}{100}=\frac{35 \times 4 h p}{100}=\frac{140 h p}{100}=1.40 h p\)