Explanation:
Step one:
given data
we are told that the expression is
v = 4.8m + 8.2
where v is the volume of gas and
m is the number of minutes it has been filling.
Step two:
Required
Asumming the volume is in Liters
the interpretation of the terms in the expression for the volume
4.8 means that for every minute 4.8L of gas enters the gas tank
hence the rate of filling is 4.8L/min
8.2 means that there is 8.2L of gas already in the tank before the filling started.