Im not sure if im correct but I think the answer is 82 hours.
The correct answer is A. $18
8 x 125% or 8 x 1.25 = 10
Add $10 to $8 and you get $18
2 wk --- 38 cm
3.5 wk --- x cm
x = 3.5 wk x 38 cm
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2 wk
x= 66.5 cm
So if it is 60 miles per hour it is basically 60 miles per 60 minutes. 
when you simplify it, it is going to be 1/1=1 The answer is 1 mile per minute
It the fourt day the total is 0.70 because
Day one: .10
Day two: you double it so .20
Day three: you double it again so .40
Day four: you add .30 so .70 is the total
