Chapter 2 - Section 2.7 - Combining Functions - 2.7 Exercises - Page 217: 35

$5$

Based on the graph, the $y-$value of $f$ at $x=4$ is $2$. Hence, $f(4)=2.$ The $y-$value of $g$ when $x=2$ is $5$. Hence, $g(2)=5$. Hence, the given composition function, $ (g\circ f)(4) ,$ evaluates to \begin{array}{l}\require{cancel} g(f(4)) \\\\= g(2) \\\\= 5 .\end{array}