Please help me answer both of these questions, I am struggling to get the right answer!!

007 (part 1 of 2) 10.0 points A black wall absorbs all the photons that strike it. How many photons per second would have to be emitted bye a laser that fires a beam of cross sectional area 1 mm perpendicularly at the wall in order to exert a pressure of 1 atm on the wall? Assume the laser which emits light of wavelength 510 nm . The speed of light is 2.99792 x 10 m/s and Planck's constant is 6.62607 x 10 34 J . S. Answer in units of photons/s. 008 (part 2 of 2) 10.0 points What would be the power (energy per unit time) of this beam? Answer in units of W