Adjust the values of [math]a[/math] and [math]b[/math] until the purple function fits the top half of the watermelon well.[br]Then uncheck "Show watermelon" and check "Show rotated region".

If you're not sure what to do next, you may find it helpful to experiment with the applet here: [url]http://higheredbcs.wiley.com/legacy/college/mccallum/0470131586/applets/ch8/hh_fig_8_16a.htm[/url][br][br]What's the volume of the watermelon?