Answer
$\{0,1,2,3\}$.
Work Step by Step
The roster method refers to writing the given elements in a list inside brackets.
The given set $\{x|x$ is a whole number less than $4\}$ contains those whole numbers which are less than $4$, which are:
$0,1,2,3$.
Using the roster method, the set is:
$\{0,1,2,3\}$.
