\(⇒\) \(P = I \times A\)
\(⇒\) \(\frac{{nh\,c}}{{t\lambda }} = IA\)
\(⇒\) \(\frac{n}{t} = \frac{{IA\lambda }}{{hc}}\) \(\left( {\frac{n}{t}} \right) = \frac{{{{10}^{ - 10}} \times {{10}^{ - 6}} \times 5.6 \times {{10}^{ - 7}}}}{{6.6 \times {{10}^{ - 34}} \times 3 \times {{10}^8}}}\)= \(300.\)