Question

read the procedural text
19 easy ways to winterize your home
11 use caulking and weatherstripping
simple leaks can sap home energy efficiency by 5 to 30 percent a year, according to the u s department of energy. that means it pays to seal up gaps with caulking and weatherstripping
which reader is most likely to find the photo in this document helpful?
a reader who is researching various types of energy efficiency
a reader who is experienced with do - it - yourself home repairs
a reader who installs windows for a living
a reader who is unfamiliar with the materials

Explanation:

A photo showing someone using caulking (a material mentioned in the text) would be most helpful to a reader unfamiliar with the materials. It provides a visual aid for identification. A reader researching energy efficiency would focus more on data (like the 5 - 30% energy loss stat). An experienced do - it - yourself reader or a window installer likely already knows what caulking looks like and how it's used.

Answer:

a reader who is unfamiliar with the materials