height of a mountain with different elevations

hello everybody,

i got a height of a mountain problem but with a little twist. thanks for any help in advance.

Determine the elevation (height above sea level) of the top of a mountain, Mount C. You take two measurements from the tops of two mountains with known elevations. All three mountain tops are in a line ( A then B then C), and all three mountain tops lie in the same plane. From the top of Mount A, with an elevation of 1240.8 feet above sea level, the angle of elevation to the top of Mount C is 16.8 degrees. From the top of Mount B, with and elevation of 1575.2 feet above sea level, the angle of elevation to the top of Mount C is 19.3 degrees. The distance along the ground from Mount A to Mount B is measured at 1742.6 feet. Find the elevation of Mount C above sea level.