Only A was incorrect

and E was also incorrect

Have checked chegg already, they don't work and I want to understand why.

(7 points) The time taken for healthy Canadian adults to complete a logic problem is believed to be Normally distributed with mean 40 seconds and standard deviation 4 seconds. It is of interest to investigate whether UBC students perform better on average than healthy adult Canadians, so the logic problem is given to a sample of 80 UBC students, and their times to solution are recorded. Part 3) Which of the following islare the parameter(s) in the context of this problem? (Select all that apply) A. The mean time for all UBC students to complete the logic problem. C] B. The mean time for the 80 UBC students to complete the logic problem. C] C. 80 C] D. The variance of the times for all UBC students to complete the logic problem. C] E. None of the above