Solve the Problem $40 \mathrm { ft }$ Wide and the Canal Is

Multiple Choice

Solve the problem.
-A cross-section of an irrigation canal is a parabola. If the surface of the water is $40 \mathrm { ft }$ wide and the canal is $26 \mathrm { ft }$ deep at the center, how deep is it $1 \mathrm { ft }$ from the edge?

A) $2.5 \mathrm { ft }$
B) $1.3 \mathrm { ft }$
C) $23.5 \mathrm { ft }$
D) $24.7 \mathrm { ft }$