clc
//
//
//

//Variable declaration
R=100   //radius
D25=0.8 //Diameter of the 25th ring
D5=0.3  //Diameter of the 5th ring
p=20    


//Calculations
lambdaa=((D25**2)-(D5**2))*10**8/(4*20*100)

//Result
printf("\n The Wavelength is %i Angstrom",lambdaa)