You would basically go back and trace all your steps, that's what I do. And if your answer seems reasonable then you have the right answer but if your work doesn't match the answer than you've messed up.
I hope I helped if I did like my answer and comment down below thx
The question is asking to choose among the following choices that states the temperature of the metal after five hours, and base on my research and further calculation, the possible answer among the following is 26 degree. I hope you are satisfied with my answer and feel free to ask for more if you have question and further clarifications
A. would be the correct option because it would have to lowest overall cost including the down payment and the weekly payments.