clear
//Given
a=51                                   //Degree
A=60                                   //Degree

//Calculation
//
b=(A+a)/2.0
c=A/2.0
u=(sin(b*3.14/180.0))/(sin(c*3.14/180.0))

//Result
printf("\n (i) The refracting angle of the prism is %0.3f  Degree", A)
printf("\n (ii) The refractive index of the material is %0.4f  ",u)