Answer:7b) 90° = m∠AODStep-by-step explanation:A 2:3 ratio, in this case, means that you have to multiply some number by two to get 24, which in this case is 12, and whatever you do to the top, you must do to the bottom as well, therefore you multiply three by 12 to get 36:⅔ = 24⁄36* 36° = m∠DOCTwo angle measures are down, so there is one to go, and that will be the m∠AOB. Here is what you do:24° + 36° = 60°If this is 60°, then we already know what the m∠AOB is, and that will be 30°, so to find the m∠AOD, we do our final addition:30° + 60° = 90°* These are what are known as Complementary Angles, which are angles that sum up to 90°.I am joyous to assist you anytime.