Sailboat Figure Labled How Far Away Is The Sailboat?

How far away is the sailboat? - sailboat figure labled

History of the problem:

They stand on the beach overlooking the water.
You will see a sailboat in the distance and want to try to figure out how much.
As a sailing enthusiast, you know, has this boat special
80-foot mast.
You choose, their 10-foot screen in order to calculate the distance to use the craft.
They lie on the sand 20 feet
away from his roof and can search the vessel.
The umbrella and neck are aligned.
Determine how the boat.