Answer
The energy of one mole of these photons is $368.1kJ$.
Work Step by Step
One mole of photons equals about $6.022\times10^{23}$ photons. Each photon would carry the energy $E$ found in part a). Therefore, the energy of one mole of these photons would be the total combination of all the energy $E$ each photon would carry.
The energy of one mole of these photons is:
$E_{mole}=(6.022\times10^{23})\times(6.112\times10^{-19})\approx3.681\times10^5J\approx368.1kJ$
