If a laser operating at a wavelength of 488 nm and a power of 123.0 mW is turned on for 18.73 minutes, how many photons has it emitted?

3.39e+20

Explanation:

a pan containing water is placed in a positio n where it is exposed to a 10 mile per hour wind. the pan contains a uniform depth of 1.27 cm of water, is quite wide, and has a length of 2.44 m in the wind direction. the water in the pan is at a constant temperature of 15.5 °c.