A 30°-60°-90° triangle and a 45°-45°-90° triangle are two drafting tools used by people in careers such as engineering, architecture, and drafting. The angles in both triangle tools are combined to make a variety of angle measures in hand-drawn technical drawings, such as blueprints. Describe or illustrate a procedure that will give the following angle measures.
a. 15°
b. 75°
c. 105°