Question 916600
{{{C = $5 + $2((u-15)/15)}}}
C = $5 + $2(47-15)/15
C = $5 + $2(32/15)  
C = $5 + $2(2 + 2/15) 
$2.00 for each additional 15 minutes (or part of 15 minutes).
C = $5 + $2(3) = $11