Multiply the 3 dimensions to find the volume, then find 4/5 of the volume by multiplying 4/5 by the volume.
12x5=60
60x20=1,200
I'm gunna convert the 4/5 to decimal to make it easier.
1,200x0.8=960
So there is a total liquid volume of 960(I'm assuming it's ounces).
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sorry if this doesn't help
