C) An undergraduate business student studies diligently in the library during dead week in anticipation of an outstanding performance on her final exams. She asks a friend to spy on her at random intervals to determine what percentage of time she is actually studying. Over the course of three days, her friend records the following observations: If the student wants a 95 percent confidence level
(z=1.96)
and a degree of precision of
+-0.08
, how many more observations are needed? (10 marks)