1. The inclination angle α=30 degrees, because the right angle (4m) opposite to the 30-degree angle is equal to half of the hypotenuse (8m).

2. AE = 2.5 * 4 =10m.

3. If C is the vertical line of AD and F is crossed, then FD=? (8*8-4*4), which is 48 square meters, with AD= 10+3+48 square meters.

4.AB？ = 4 * 4+10 *10 =116, so AB=? 1 16 is the square of 1 16.