Answer
a. The domain is $A=\{-1,0,1\}$ and the codomain is $B=\{t,u,v,w\}$.
b. $F(-1)=u, F(0)=w, F(1)=u$
Work Step by Step
Recall that, for a function, every value in the domain must be mapped onto a value in the codomain, but not every value in the codomain must be paired with a value from the domain.