Q:  How much more power does the hot star produce at a
          wavelength of 550 nm?


          At a wavelength of 550 nm, the graph shows the intensity
          of the hot star as about

                hot:   10^(15)        J/sq.m.*s*m

          while that of the cool star is about

                cool:  10^(13.5)         J/sq.m.*s*m

        
          Therefore, the hot star produces more radiation by a 
          factor of


                    10^(15)
                   ---------    =   10^(1.5)  ~  31
                   10^(13.5)