Write the Word or Phrase That Best Completes Each Statement $f ( x ) = \tan x$

Write the word or phrase that best completes each statement or answers the question.
- $f ( x ) = \tan x$ is defined over the interval $\left[ 0 , \frac { 3 } { 2 } \right]$
(a) Approximate the area A by partitioning $\left[ 0 , \frac { 3 } { 2 } \right]$ into 4 subintervals of equal length and choosing $u$ as the left endpoint of each subinterval.
(b) Approximate the area A by partitioning $\left[ 0 , \frac { 3 } { 2 } \right]$ into 8 subintervals of equal length and choosing us the right endpoint of each subinterval.
(c) Express the area A as an integral.
(d) Use a graphing utility to approximate this integral to three decimal places.