You may need to use the appropriate appendix table or technologyto answer this question.

Consider a multiple-choice examination with 50 questions. Eachquestion has four possible answers. Assume that a student who hasdone the homework and attended lectures has a probability of 0.70of answering any question correctly.

(a)

A student must answer 45 or more questions correctly to obtain agrade of A. What percentage of the students who have done theirhomework and attended lectures will obtain a grade of A on thismultiple-choice examination? Use the normal approximation of thebinomial distribution to answer this question.

(b)

A student who answers 34 to 39 questions correctly will receivea grade of C. What percentage of students who have done theirhomework and attended lectures will obtain a grade of C on thismultiple-choice examination? Use the normal approximation of thebinomial distribution to answer this question.

(c)

A student must answer 28 or more questions correctly to pass theexamination. What percentage of the students who have done theirhomework and attended lectures will pass the examination? Use thenormal approximation of the binomial distribution to answer thisquestion.

(d)

Assume that a student has not attended class and has not donethe homework for the course. Furthermore, assume that the studentwill simply guess at the answer to each question. What is theprobability that this student will answer 28 or more questionscorrectly and pass the examination? Use the normal approximation ofthe binomial distribution to answer this question.