You are not logged in.
A standard measure of test anxiety is knnown to produce a u=19. In the sample you draw of 86 the mean is equal 17.5 with a standard deviation s=10.
In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.