Model practical situations with linear relations

A tank initially contains 10 litres. Water enters at a constant rate of 4 litres per minute, with no other flow

Let \(t\) be elapsed time in minutes and \(V\) the remaining water volume in litres

Use this model only for \(0\le t\le 14\), allowing fractional times

Input for prediction, measured in minutes: \(t=7\)

Separately test whether \(t=6\) is allowed by the stated input domain