Explanation:

- You have a 10 meters tall building.

- The angle of elevation from the bottom of the building is 45°.

- This suggests the height from the bottom to the tower's top is the same as the horizontal distance to the tower, due to the tan(45°) = 1.

- From the top of the building, the angle is 30°.

- This indicates the distance from the building top to the tower's top relates by tan(30°) = height/distance, with tan(30°)=1/v3.

- Use the 45° angle to find the common distance, then apply tan(30°) to find the remaining height.

- Upon calculation, the height from the building top is 13.65 meters.

Correct Answer: 13.65