The min. energy needed to break a C-Br bond is 288000mol^-1. If one has access to laser with 3 output wavelengths 266,1065,800nm, which wavelength(s) can be used to break that bond?

I keep getting 417nm for the wavelength (which is none of the outputs) but the answer is 266nm. Thank you!

Using 6.626E-34 for h, 3E8 for c and 6.02E23 for A's number, I get essentially your answer of 416 nm also.