Answer can get 2 points, if the answer is accepted, you will get reward points and reward 20 points. First, calculate the inclination angle of light, tana =11.2 = 5/6, then for a strong section, the horizontal shadow blocked by the wall is 2/(5/6)=2.4, so the total length of the original horizontal shadow is 2.4+. So the length of flagpole is12 * (5/6) =10m.