Number of photons of equal energy emitted per second by a 6 mW laser source operating at 663 nm is ____. (Given: h =6.63 × 10^-34 J. s and c =3 ×…

Number of photons of equal energy emitted per second by a $\displaystyle 6$ mW laser source operating at $\displaystyle 663$ nm is $\displaystyle \_\_\_\_$. (Given : $\displaystyle \mathrm{h}=6.63 \times 10^{-34} \mathrm{~J} . \mathrm{s}$ and $\displaystyle \mathrm{c}=3 \times 10^8 \mathrm{~m} / \mathrm{s}$ )