A gutter is to be made of a strip of metal 26.1 inches wide, with the cross-section having the form of an isosceles trapezoid as shown below. Find the depth $\displaystyle {h}$ that gives the maximum cross-sectional area.



What is the length of $\displaystyle {a}$ in the picture? Select an answer in^3 in^2 in

The depth, $\displaystyle {h}$, that gives the maximum cross-sectional area is Select an answer in in^2 in^3

The maximum cross-sectional area is Select an answer in^2 in in^3