power Questions

The number of photons per second on an average emitted by the source of monochromatic light of wavelength $600\text{nm}$, when it delivers the power of $3.3\times 10^{-3}\text{watt}$ will be ($h=6.6\times 10^{-34}\text{Js}$):

Water falls from a height of $60\text{m}$ at the rate of $15\text{kg/s}$ to operate a turbine. The losses due to frictional force are $10\%$ of the input energy. How much power is generated by the turbine? ($g=10{\text{m/s}}^2$)