used for randomly selected values X and Y from two populations
For comparing two small sets of observations,
gives insight into the meaning of the U statistic,
I dont think you pit the entire question there.
Because without the shot, your body would react differently making you contagious. Therefore, you would make others around you sick.
Answer
The periosteum is a membrane that covers the outer surface of all bones, except at the articular surfaces (i.e. the parts within a joint space) of long bones.
Explanation: