Answer:
$ 7.44
Step-by-step explanation:
20m rope costs $12.40
So, 12m costs = 12.40 x 3/5
= $ 7.44
b=5..............is the answer
Let H be height of a cliff
h depth of the pond
Total distance traveled (S)= H+h
S=20+13
S=33m
3 months
