this problem is related to composition of functions

Question

Suppose a ship is sailing at a rate of 35km/h parellel to a straight shoreline. The ship is 10km from shore when it
passes a lighthouse at 11 am.
a) Let k be the distance between the lighthouse and the ship. Let d be the distance from the ship has
travelled since 11 am. Express k as a function of d. Please include a diagram.
b) Express d as a function of t, the time elapsed since 11am.
c) Find . What does this function represent?

Answer 1

d and 10 are the legs of a right triangle

k is the hypotenuse

d = 35t

k = √[(35t)² + 10²]