What is rapid change in mood? ? ? (i already know it but just asking)

Mood swings refer to rapid changes in mood. The term may refer to minor daily mood changes or to significant mood changes as seen with mood disorders such as major depression or bipolar depression. Mood swings can also occur in women who suffer from premenstrual syndrome or premenstrual dysphoric disorder.

Explanation:

depression is an ongoing sadness\lack of motivation. you feel and feel like its never going to get better. you're so sad to the point you think of death.

anxiety is an ongoing feeling of paranoia\ feeling like everyone is watching you and making fun of you. you get nervous easily and feel like the room is spinning.  

yes, they cause death every year. its a long, exhausting battle. only few make it through as sad as it sounds.

explanation:

well say a good goal is to do 150 sit ups in a week! or 90 pull ups a day. even 60 push ups in a month these are all fair goals!