How to calculate electric bill?

CODE

How to calculate electric bill?

Program for Electric bill. Follow the instruction:

If units<=200 -> 2

If units<=400 -> 3

If units<=600 -> 4

Else 5

int main()

{

    float unit,bill,tax,gross;

    printf("\n enter number of units:");

    scanf("%f",&unit);

    if(unit<=200)

        bill=unit*2;

    else if(unit>200 && unit<=400)

        bill=unit*3;

    else if(unit>400 && unit<=600)

        bill=unit*4;

    else

        bill=unit*5;

    tax=bill*10/100;

    gross=bill+tax;

    printf("\n gross bill=%f",gross);

}

Output:

enter number of units:

500

 gross bill=2200.000000