17. Before rock climbing, Michelle wants to know how

high she will climb. She places a mirror on the

ground and walks backward until she can see the

top of the cliff in the mirror. She drew a sketch of

the situation. What is the height of the cliff?

Top of cliff

х

mirror

Michelle

5.5 ft

4 ft

16 ft

A. 16.5

B. 17.5

C. 20

D. 22