The average score for a business examination comprising 300 students is 54%. If the marks are normally distributed with a standard deviation of 8%, determine the number of students scores above 70%.

Answer 1

well, 70 is 2 std above the mean.
Look that up in your Funk and Wagnall's (or, more productively, in your Z table).

Answer 2

Is there a hypothesis you would like to see tested? Comment on why it has not been tested, and briefly describe how you would get the data for the test.