To find the probability values increase of raw data, binomial, normal.

A biology teacher had noted that the scores on a standard examination attained by students from her past classes had a mean of 74 and a standard deviation of 14. The teacher decided to use a new book. She supposed this would increase the mean, other than that the standard deviation would remain at 14. Using new book, a class of 50 students scored a mean of 76 on the standardized examination.
  (i) Find the probability that a class of 50 students using the new book will have a (sample) mean as large as or larger than 76 if the new book were equivalent to the old book (i.e., if U= 74 and O = 14 for all students using the new book).
  (ii) Do you think that there is evidence to support the teacher's claim that the new book is superior? {Hint: use part (a).}