I need help with virtual memory problem
A quick search reveals that


POFS is page offset.
VPN is virtual page number.
PFN is page frame number.


Since the page offset is 13 bits long, assuming that the page is byte-addressed, the conclusion is that page size is $2^{13}$ bytes.

I trust that you can solve the other parts in a similar way, especially having been taught these concepts in class.