How did Escalante express confidence in his students and support their efforts? Check all that apply.

He tells students that if they bring ganas $($desire$),$ they can earn a college credit$$earning score on a difficult math exam.

He welcomed observers who wanted to benchmark the successful AP program at Garfield High School.

He stays after school to work with students and goes into the community to meet with their families.

He was an expert on teaching math, having taught it in Bolivia and earned credentials to teach the subject in the United States.