Question 1123785
if the call lasts 3 minutes or less, c = x

if the call lasts more than 3 minutes, c = x + y * (m-3).


for example, assume x is $1.00 and y is $.25 per minute.


call lasting less than or equal to 3 minutes costs $1.00.


call lasting 20 minutes costs $1.00 + $.25 * 17 = $1.00 + $4.25 = $5.25.