Statistics
posted by Lynn .
I have a question that involves explaining what is wrong in each of the following situations:
(a) A random sample of size 20 is taken from a population that is assumed to have a standard deviation of 12. The standard deviation of the sample mean is 12/20.
(b) A researcher tests the following null hypothesis: Ho:mean of the sample = 10
(c) A study with a sample mean = 48 reports statistical significance for Ha : u > 54.
(d) A researcher tests the hypothesis Ho : u = 50 and concludes that the population mean is equal to 50.
Help is appreciated I have answers already, but wanted to know if they were right. Thank you!!!!

It usually works the other way around; you give us your answer and we (the Jiskha volunteers) tell you whether you are right or not). We want to guide your thinking rather than do your homework for you.

Ummm, guiding our thinking doesn't work. I'm student teaching right now and I've been a student for year, sometimes you have to give the student the answer in order for them to figure out for themselves WHY it is right.