Write down all the subsets of the following set: $\{a, b\}$

Consider the experiment of rolling a die. Let $A$ be the event 'getting a prime number' and $B$ be the event 'getting an odd number'. Write the sets representing the events $A$ and $B$.

Write the following interval in set-builder form: $[6, 12]$

The set $\{n(n+1)(2n+1) : n \in \mathbb{Z}\}$ is a subset of:

List all the elements of the following set:
$B = \{ x : x \text{ is an integer}; -\frac{1}{2} < x < \frac{9}{2} \}$

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