PLEASE HELP TO SOLVE!?

angel falls in venezuela, the highest waterfall in the world, is oberseved from a point level with the base of the falls. from this point the angle of elevation to the top of the falls is 65 degrees. the observer then walks straight toward the falls to a second point that is also level with its base and finds the angle of elevation to be 85 degrees. if the two points of observation are 1216.8 feet apart, find, to the nearest foot, the height of the falls.