68-89

I’m missing the context. Do you want solutions for exam problems numbered 68–89 from a specific book or course? If you can share the exact problem statements (or a photo/text of problems 68–89), I’ll work through them step by step.

If you can’t share them, tell me:

• the subject (e.g., Calculus, Linear Algebra, Physics, CS)
• the chapter or topic range those problems come from

I can then:

• provide a general approach or template for that type of problem
• generate practice problems of similar style
• or wait for you to paste the exact 68–89 problems and I’ll solve them with explanations.