Martha’s maximum lung capacity is \(7.4\) liters. If her lungs are full and she exhales at a rate of \(0.8\) liters per second, when will she have \(2.76\) liters of air left in his lungs?

Assume \(s\) seconds later, there would be \(2.76\) liters of air left in Martha’s lungs. Write an equation to model this scenario. There is no need to solve it.