Question

you notice that your best friend often picks up quarrels with jonior students in the school bus you feel that most times unreasonable

Answer 1

he probably does it because he thinks it's cool. or perhaps this same thing has happened to him when he was a junior. u can talk abt this with him and tell him that in all these quarrels he is the one who is unreasonable. this may lead to people thinking he is rude and they would start ignoring him.