Vegetable oil is used in a food processing factory to prepare flour

of instant bread. A stirred tank is used to store the oil; during operation of the

process, oil is pumped from the tank at a rate of $4\mathrm{.}8$ l h

$-1$

$.$ At $8$pm during the shift

night, the tank is mistakenly connected to a drum of cod liver oil that is

then pumped to the tank where only the vegetable oil used in the process should be pumped.

process. The volume of vegetable oil in the tank at $8$ pm is $60$ l$.$