I’m ready to help with problem 4, but I need the question or topic.
Please paste the full problem statement (or a screenshot) for item 4, or tell me the subject and the type of question (e.g., math, physics, CS, chemistry). I can then walk you through a step-by-step solution and point out common pitfalls.
If you’d like, I can also generate a quick 4-type practice problem in your subject and solve it with you.