Make correct statements by filling in the symbols $\subset$ or $ \not\subset $ in the blank spaces:

$\{a, b, c\} \ldots\{b, c, d\}$

Let $A=\{a, e, i, o, u\}$ and $B=\{a, b, c, d\} .$ Is $A$ a subset of $B ?$ No. (Why?). Is $B$ a subset of $A ?$ No. (Why?)

Write down all the subsets of the following sets

$\{ a\} $

Write down all the subsets of the following sets

$\{ a,b\} $

Let $A=\{1,2,3,4,5,6\} .$ Insert the appropriate symbol $\in$ or $\notin$ in the blank spaces:

$ 0\, ........\, A $

State whether each of the following set is finite or infinite :

The set of lines which are parallel to the $x\,-$ axis