Answer
(a) $Work = 1.5~J$
(b) $Work = 1.125~J$
Work Step by Step
(a) The area under the force versus displacement graph is equal to the work done by the force:
$Work = \frac{1}{2}F_{max}~x$
$Work = \frac{1}{2}(15~N)(0.20~m)$
$Work = 1.5~J$
(b) On the graph, we can see that the area under the graph between $x= 0.10~m$ and $x = 0.20~m$ is 75% of the total area under the graph between $x = 0$ and $x = 0.20~m$:
$Work = (0.75)(1.5~J) = 1.125~J$
