Answer:
{1, 2}
Step-by-step explanation:
Hello there!
The following set
{x | x ∈ N, x < 3}
means: all x given that x is a natural number and x is less than 3.
Natural numbers are: 1, 2, 3, 4, 5, et cetera. 3 is not less than 3, so the list is: {1, 2}