Answer:
C. 13ft
Step-by-step explanation:
13 foot
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21/40, 17/20, 29/40, 3/4, 4/5
21/40 = 10.5/20
29/40 = 14.5/20
17/20 = 13.5/20
3/4 = 15/20
4/5 = 16/20