In one study cited in the textbook (chen, et al., 2010), cortisol levels among low-income children increased when they experienced more daily hassles. therefore, cortisol levels are correlated with the number of daily hassles low-income children experience.

positively

Explanation:

There is a positive correlation when two variables move in the same direction. When one increases, the other one does too.

In this case the two variables are: cortisol levels and the number of daily hassles.

In the study cortisol levels increased when children experienced more daily hassles. The more hassles, the higher the cortisol levels. Both variables move in the same direction and there is a positive correlation