In each of the following, determine whether the statement is true or false. If it is true, prove it. If it is false, give an example.
If $A \not\subset B$ and $B \not\subset C,$ then $A \not\subset C$
State whether each of the following set is finite or infinite :
The set of lines which are parallel to the $x\,-$ axis
Let $A=\{1,2,\{3,4\}, 5\} .$ Which of the following statements are incorrect and why ?
$1 \in A$
Let $S=\{1,2,3,4\}$. The total number of unordered pairs of disjoint subsets of $S$ is equal to
Examine whether the following statements are true or false :
$\{ a\} \in \{ a,b,c\} $