Question

State which of the following are null or empty set?

$\left\{Menover300yearsold\right\}$

Answer 1

A set that contains no member is called the empty set. It is also called the null set.

It is denoted by $\left\{\right\}$or $\phi$

Given set:

$\left\{Menover300yearsold\right\}$

There is no men who is over $300years$ old, the given set contains no element.

Hence, The set of $\left\{Menover300yearsold\right\}$ is Null or empty set.