The height of the roof is calculated by the curvature ratio. To calculate this part more accurately, you can find the ratio of the house in the way shown in the example and record it in the appropriate cell, and then get the result. Example: If the height of your house is 3 meters and the distance from the corner of the roof to the center of the house is 9 meters, the calculation is based on the principle of reciprocity as follows. If 9 --- 3 (3 \ 9) is 12 --- X (X \ 12), then by finding the simple equation X, you denote X by 12 in the corresponding cell. In this calculation, the curvature ratio will be 4/12.