For What Wavelength Does A $100 - \mathrm { mW }$

Multiple Choice

For what wavelength does a $100 - \mathrm { mW }$ laser beam deliver $1.6 \times 1017$ photons in one second? $( c = 3.0$ $\left. \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } , h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$

A) $340 \mathrm {~nm}$
B) $350 \mathrm {~nm}$
C) $320 \mathrm {~nm}$
D) $330 \mathrm {~nm}$