I need help only on these 3 questions. I need with steps on how to get the answer.

A distribution of grades in an introductory statistics course (where A = 4, B = 3, etc) is: X 0 1 2 3 4 P(X) 11 .18 .2 .32 19 2) What is the probability that a student has passed this class with at least a C (the student's grade is at least a 2)? A) .2 B) .29 C) .52 D) .71 E) None of the above 3) What is the probability(to the nearest .01) that a student has an A (4) given that he has passed the class with at least a C (2)? A) .19 B) .27 C) .42 D) .71 E) .95 4) What is the expected grade in the class? A) 2.0 B) 2.1 C) 2.5 D) 3.0 E) None of the above