What revision changes the tone of the sentence from informal to formal

The very beginning will because it is the tone that the audience pays attention to.

(i can't select because there is no options but, i will answer) using evidence effectively. most of the assignments you will do in university will ask you to make an argument, to take a stance, or to prove a hypothesis. the best way to do this is to research the topic, develop a thesis statement, hypothesis, or claim and then use evidence to support this claim.

he will find out what went wrong or happened and how.