At a Certain University, the Average Cost of Books Was

Multiple Choice

At a certain university, the average cost of books was $370 per student last semester and the population standard deviation was $80. This semester a sample of 45 students
Revealed an average cost of books of $390 per student. The Dean of Students believes
That the costs are greater this semester. What is the test value for this hypothesis?

A) 0.44
B) 0.25
C) 11.25
D) 1.68