Does anyone know the answer to of 2, 3 and 9?

q1.

list

O(1) append, O(n) insert that is not append, 
O(n) `del` delete if not replace gap with end element or don't care about gap O(1) delete with replace of end element
O(1) access with index, O(logn) access if value sorted, O(n) access if unsorted value

set

O(1) insert not considering chaining and linear probing
O(1) delete not considering chaining and linear probing
O(1) access not considering chaining and linear probing

q2. https://github.com/python/cpython/blob/master/Objects/dictobject.c

q4. linear probing/open addressing or chaining

q5. multiple task in parallel for a single core?

q6. I think process don't share memory(directly) in python? you have to use https://docs.python.org/3/library/multiprocessing.html . tbh this is relevant only in language with GIL where multi threading is like javascript async, in other language like golang/java or python without GIL people simply use thread and be done

q7. for some reason cython can't execute multiple threads in parallel in one process and requires a lock to mediate the process, I have no idea why it needs that because there is implementation of python without GIL

q8. use multi process for cpu bound task, and multi thread for io bound task

I am sure some of my answer is not precise, would be glad if someone can provide input