B. Each container has a capacity of 2 gallons
This is just based on proportions.
We are told that 6 thermo flasks with each flask being ⅓ full.
⅓y × 6 = 4
Where y is the capacity of gallons per flask.
2y = 4
y = 4/2
y = 2 gallons
Thus, each flask has a capacity of 2 gallons.
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