Boolean Question

Pdf.pdf (226.8 KB)
Problem.gh (23.1 KB)
Question.gh (16.4 KB)
Hello. I am facing issues with some practice questions.
For Question 1 Boolean in the pdf, my answer is one open polysurface instead of a closed one. I’m not sure how to fix that.
For Question 2, I tried a lot but cant seem to get the desired pattern.
In Question 3 as well, my solver doesn’t give a result.
If someone can tell me my mistakes or help in anyway I’ll appreciate it.
Thank you.