The laser in Blu-Ray players emits light at 405 nm. Lasers can emit light in short bursts called pulses.

The laser in Blu-Ray players emits light at 405 nm. Lasers can emit light in short bursts called pulses. The number of photons emitted during a pulse is dependent on the length of the pulse as well as the power/intensity of the laser. Calculate the total energy emitted, in J, for a blu-ray laser during a laser pulse if the laser emitted 7.85E-8 (7.85 × 10-8) moles of photons. Enter your answer with 3 significant figures and in scientific notation(X.XXEYY). Do not include units with your answer.