Jill wants to get more active, but is having trouble motivating herself to engage in more physical activities. she talks with a friend and they decide to motivate each other to be more active by documenting the number of physical activities they engage in each week. if they meet a certain requirement, they reward themselves with a gift or a leisure activity. which approach are jill and her friend using to motivate themselves?

The approach that Jill and her friend is doing the motivation and reward system.  In this system, a set of goal is being targeted and a reward is being accomplished after reaching the goal. In this case, Jill and her friend reward themselves by getting a gift or doing a leisure activity.

Cognitive psychology focuses on studying D. thoughts and their relationship to our experiences and our actions.
Cognition refers to thoughts, ideas, and understanding of the world. Therefore, cognitive psychology has to do with how our thoughts might influence our experiences and actions, and vice versa. It studies many mental processes in our brains, such as memory, perception, thinking, creativity, etc.