Answer
Yes, she is correct.
Work Step by Step
On page 1082 it’s explained that when light enters a medium that has a higher index of refraction (e.g., from vacuum to air), it slows down, and the light ray bends toward the normal.
As you can see from Figure 33.10, this means that the sun always appears higher in the sky than it actually is.
So, in the morning, the sun appears above the horizon early, and in the evening, it lingers above the horizon longer than it would if no air were present. That is what she means.
Refraction makes the day longer, by a few minutes, compared to if there were no atmosphere.
