I am really struggling with a few regression assignments and I have been trying to watch all the videos that I can but I am still not any clearer.

I am really struggling with a few regression assignments and I have been trying to watch all the videos that I can but I am still not any clearer. Would it be possible to help with step by step walk through with the data and questions below? I have another 3 assignments on regression and I am really worried that I am not going to understand. Thank you!