What temperature, in degrees Celsius, is a blackbody whose emission spectrum peaks at...?

Part A: What temperature, in degrees Celsius, is a blackbody whose emission spectrum peaks at 350nm? Part B: What temperature, in degrees Celsius, is a blackbody whose emission spectrum peaks at 4.30um (micrometers)? Any help would be greatly appreciated. Looking for an answer as well as an explanation on how to solve the problem. Thanks!