For the first transportation way, let’s assume:
The oil tank truck can load five barrels of gasoline.
It spends two minutes to take out a barrel of
gasoline from the oil depot.
It spends five minutes to pour a barrel of gasoline to
the oil tank truck.
It spends one day for the oil tank truck to come to
and back from the gas station.
It spends five minutes to unload a barrel of gasoline
from the oil tank truck.
It spends two minutes to pour a barrel of gasoline
into the gas station.