What is the relationship between the mean of a sampling distribution and the population mean. Please provide an explanation.

Kindly help me to Illustrate this relationship via the following example:

A 5-a-side water-polo team consists of five players: Michael, LeBron, Kobe, Kareem and Magic who weigh 240, 225, 201, 232 and 220 pounds respectively. Find all possible random samples with replacement of size two and compute the sample mean for each one. Use them to find the probability distribution, the mean, and the standard deviation of the sample mean.