Question 1090046
Bottom right triangle, angles 90, 50, 40 degree; the 40 degree angle at bottom of the cliff.


Distance from cliff to ship deck,  {{{15*(sin(40)/sin(50))}}}.




Upper right triangle, angles 90, 70, 20; the 20 degree angle at the top of the cliff.
Leg along the cliff, y,
{{{y/sin(70)=(15*(sin(40)/sin(50)))/sin(20)}}}-----simplify and solve for y and compute.


Cliff total height,  y+15.