Business Finance Homework Help

Hi, I have an optimization problem I’m meant to do in Excel with Solver. In my version I think the model is setup incorrectly, which is why Solver is unable to provide a solution. I think I might be off with my decision variables. The original problem given is on tab 1, with my initial run at it on tab 2. For decision variables I used production quantities of each vehicle. Is that wrong? What is the decision/input variable?

Thank you so much for your help.