1. The problem statement, all variables and given/known data A trough in the shape of an isosceles trapezoid is 30 cm wide on the bottom, 80 cm on the top, 50 cm tall, and 10 cm long. It is being filled with water at 0.2 cm3/min. How fast is the water level rising when the water is 30 cm deep. 3. The attempt at a solution Well I used a similar triangle deal to eliminate the 'base' of the triangles on each side of the rectangle that make up the trapezoid. Then I wrote this: v=((30h)+(.5h)(h)(2)) * 10 but when I go to derive it, it all hits zero...something is wrong here. What is it?