Your roommate is acting very strangely. although she has not slept much in the past few days, she says she is on top of the world. she has cleaned and re-cleaned her closets several times. she also took all her savings and invested it in a questionable financial venture. this period of non-stop activity has lasted for well over a week and is in sharp contrast to the depression and fatigue she exhibited earlier this semester. your roommate is exhibiting symptoms of
a. bipolar disorder
b. generalized anxiety disorder
c. panic disorder
d. borderline personality disorder

A. Bipolar disorder

Explanation:

Bipolar disorder is a brain disorder  characterized by massive mood swings that occurs to a person within short period of time.

This will make them act extremely hyper and happy at one moment (such as the roomate when she is saying she is on top of the world)  and suddenly revert back to become extremely depressed several days later. Both the swings tend to happen without any justifiable reason.

Currently, there is no cure for bipolar disorder but the patients can take medications to maintain their emotional stability.

answer; ethnocentric;

answer; self-serving bias;