A flagpole casts a 13-foot shadow on the ground when the sun is at a 68° angle of elevation. Which of the following expressions can be used to determine the height (h), in feet, of the flagpole? (Assume the flagpole is perpendicular to the ground.)

A. cos68°=h13
B. cot68°=h13
C. sin68°=h13
D. tan68°=h13