Calculate the wavelength of peak emission for a typical sunspot and compare it to that of the photosphere. How many times brighter is the photosphere than a typical sunspot? (Hint: Assume the photosphere and a sunspot are good blackbodies for these calculations.)
They need to provide you with data on the typical temperature of a sunspot, compared to that of the photosphere.
Use the Wien displacement law (Lambdamax*T = constant) for the first question and the Stefan-Boltzmann (T^4) law for the second question.