t	0	7	11.5	14.5	18.5	20
r(t) per	13.25	15.5	13	13.25	13.75	15.25

A.  Use the Trapezoidal Rule with sub-intervals indicated by the table to estimate $\displaystyle {\int_{{0}}^{{20}}}{r}{\left({t}\right)}{\left.{d}{t}\right.}$.



B.  What are the final units on your estimate?