Number of Different types of Subsets

Q. Set $A$ has $m$ elements and set $B$ has $n$ elements.If the total number of subsets of $A$ is $112$ more than the total number of subsets of $B,$ then the value of $m\times n$ is

Q. Set $A$ has $m$ elements and set $B$ has $n$ elements.If the total number of subsets of $A$ is $112$ more than the total number of subsets of $B,$ then the value of $m\times n$ is

Q. The number of subsets of the power set of $A$, where $A=\{x:x\in N-3\le |x|<4\}$ will be

Q. Let $S=\{0,1,5,4,7\}$. Then the total number of subsets of S is

1. 64
2. 32
3. 40
4. 20