Sets — NDA Mathematics PYQs

If $A$ and $B$ are non-empty subsets of a set, and $A^c$ and $B^c$ represent their complements, then which of the following is/are correct?
I. $A-B=B^c-A^c$
II. $A-B^c=A^c-B$
Select the answer using the code given below.

In a class of $45$ students, $34$ like to play cricket and $26$ like to play football. Further, each student likes to play at least one of the two games. How many students like to play exactly one game?

Set $X$ contains $3n$ elements and set $Y$ contains $2n$ elements, and they have $n$ elements in common. How many elements does $(X-Y)\times (Y-X)$ have?