//Chapter-2,Example2_6_2,pg 2-32

wavelength=481                                 //wavelength of light 

m=3                                           //for third order 

N=620*5.05                                    //number of lines per meter

d_wavelength=wavelength/(m*N)

printf('\n The smallest wavelength interval is  d_wavelength = %.4f nm\n',d_wavelength)