Question

if monday is considered as first day of the week and tuesday as second day and so on .find the range of the week

Answer 1

range=highest value - lowest value
            =7-1
              =sunday-monday
           =6=saturday
 range=6=saturday

Answer 2

If Monday is considered as first day of the week and Tuesday as second day and so on. The range would be Saturday, 

To calculate range you subtract the highest value from the lowest value.
 
range = highest value - lowest value

            =7-1
              ⇒ sunday-monday
             ⇒ 6 =saturday

 range = 6 
=saturday