Vertical Antennas Ground Radials Need Help..can Someone Solve This Problem For Me Plz?

Need help..can someone solve this problem for me plz? - vertical antennas ground radials

A vertical antenna mounted on a pole 40 feet. From a point on the ground 78 meters from the base of the mast hole edge and the antenna at an angle of 10.7 degrees. Find the length of the antenna to the nearest tenth of a foot.

A) 20.6 m B) -25.3 m C) 33.2 m D) 11.7 m