I am studying for a vector calc final and one of the old exams has a question I do not know how to attack with calculus or anything else for that matter!

The length of a box is increasing at 2 feet per minute. The width is decreasing at 3 feet per minute. While the height is increasing at 4 feet per minute. Find the rate of change of the volume when

the length is 10 feet

the width is 15 feet and

the height is 18 feet

Thanks and good luck to all of you facing finals! Frostking