A) 10.4 liters
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First, calculate how much fuel is already in the tank.
If the tank is 4/5 full, then it contains:
- 4/5 * 52 litres = 41.6 litres of fuel
To find how many more liters are needed to fill the tank, we subtract the amount of fuel already in the tank from the tank's maximum capacity:
- 52 litres - 41.6 litres = 10.4 litres
Therefore, the answer is 10.4 liters (Option A).