Suppose that the universal set $\displaystyle {U}$ is the set defined as $\displaystyle {U}={\left\lbrace{1},{2},{3},{4},{5},{6},{7},{8},{9},{10}\right\rbrace}$.

Write the sets $\displaystyle {A}$ and $\displaystyle {B}$ out in roster notation.

$\displaystyle {A}={\left\lbrace{x}\in{U}{\mid}\right.}$ x is an even number $\displaystyle {\rbrace}={\lbrace}$ $\displaystyle {\rbrace}$

$\displaystyle {B}={\left\lbrace{x}\in{U}{\mid}\right.}$ x is a prime number $\displaystyle {\rbrace}={\lbrace}$ $\displaystyle {\rbrace}$



Find each of the following:

$\displaystyle {n}{\left({A}\right)}=$

$\displaystyle {n}{\left({B}\right)}=$