Answer:
15
Step-by-step explanation:
number 2)
Explanation step by step
Hello,
Using Thalès 's theorem:
Let's h the height of the monument.
If you don't know what is the Thalès's theorem,
imagine that the similar triangles.
178
area of big rectangle : 143
area of small rectangle:20
area of triangle : 15
143+20+15= 178