Operations on Sets

If $\mathrm{A}=\{1, 2, 3, 4, 5, 6, 7\}$, then the number of proper subsets of $\mathrm{A}$ is

Find the number of subsets, number of proper subsets, and the number of improper subsets of the set $A=\left\{a,b,c,d,e\right\}$.

$A,B,C$ are three disjoint sets. $A$ has $6$ elements, $B$ has $4$ elements, $C$ has $8$ elements, the cardinal number of $\left(A\cup B\cup C\right)$ is ___.

$A,B$ are two disjoint sets. $A$ has $10$ elements, $B$ has $3$ elements. Find the number of elements in $\left(A\cup B\right)$. 

Find the union of the two disjoint sets $A=\left\{1,3,5,7\right\}, B=\left\{4,8,12,16\right\}$

Two finite sets have $m$ and $n$ elements. The number of subsets of the first set is $240$ more than that of the second. The values of $m$ and $n$ are respectively

Two finite sets have $m$ and $n$ elements. The number of subsets of the first set is $120$ more than that of the second. The values of $m$ and $n$ are respectively

It is given that $A=\{1, 2, 5\}$, $B^{\text{'}}=\{2, 4, 5\}$ and $A^{\text{'}}=\{3, 4\}.$ Find $\mathrm{n}\left(A\cup B^{\text{'}}\right)$and $\mathrm{n}\left(A^{\text{'}}\cap B\right)$.