PLEASE HELP WILL FRIEND AND WILL GIVE POINTS

Read the paragraph below.

Ms. Joon, a substitute teacher, breezed into the classroom and settled at the teacher’s desk. She reviewed the plans that had been left for her, making careful notes in the margins. She wrote her name on the whiteboard and greeted students as they entered. When one student grumbled, "Oh no, a sub?”, she cheerfully asserted that everything would be "business as usual.”

What inference can be drawn about Mrs. Joon?

She is hoping to make friends with the students.
She is confident and prepared for her job.
She is well-educated and very intelligent.
She is trying to disguise her nervousness.