A pilot of a plane flight with height 1.300 meters above the sea, saw a ship sail with angle of depression 40 degree. Specify the distance of the vessel to the point at sea level which is right under the air !
We can find the horizontal distance, h, from the plane to the ship as follows :
tan (40) = 1300 / h .....rearrange as.....
h = 1300/tan(40) = about 1549.3 m
