Dollars is the dependent quantity because the amount you pay depends on how many gallons you've pumped.
70℅ = 14
100 = X
70X = 1400
X = 1400/70
X = 20
20 Euros is the full price
ANSWER

EXPLANATION
The given expression is

The middle radical contains a perfect square.



Note that:


One thing for sure it is not b,d,c its a