It is not to scale, but it illustrates the quantities we are working with. Drawing out the problem is always a good idea in trigonometry.
What you know is the angles and the altitude, which constitutes the sides opposite to the known angles. Since you know the leg opposite to the angle and need to find the legs adjacent to the angles of these two right triangles(which I have labeled D1 and D2) which trigonometric ratio do you need to use?
In order to solve these without a calculator, you are going to need to use the addition laws and know the exact values of the special angles:
The last step is to find the distance in meters the helicopter traveled (subtract D2 from D1) in one minute and then convert that into kilometers per hour.