Answer
$3$
Work Step by Step
Based on the table, the $y-$value of $f$ at $x=1$ is $2$. Hence, $f(1)=2.$ The $y-$value of $f$ when $x=2$ is $3$. Hence, $f(2)=3$. The given composition function, $
f(f(1))
,$ evaluates to
\begin{array}{l}\require{cancel}
f(2)
\\\\=
3
.\end{array}