A ladder 15m long leans against a vertical wall so that its foot is 9m from the wall. The ladder, wall and ground form a right-angled triangle. Let θ be the angle between the ladder and the ground.
a. (i) Calculate the height (in metres) that the ladder reaches on the wall.
b. (ii) Using the dimensions of the triangle, find sinθ, cosθ and tanθ in simplest fractional form.
c. (iii) Determine the value of θ correct to the nearest whole degree.