The average grade of graduating engineering student has historically been 78 with a standard deviation of 5. A random sample of 50 current graduating engineering student in the present has an average...

The average grade of graduating engineering student has historically been 78 with a standard deviation of 5. A random sample of 50 current graduating engineering student in the present has an average grade of 80 and the standard deviation remains the same. Using two-tailed test

a.) What are the hypotheses?

b.) What is the t-value/z-value?

c.) Is there reason to believe that there has been a change in the average grade of the graduating student?