Data Collection and Descriptive Statistics

List a few “DO’s” and “DON’T’s” of the Data Collection process.
What is the difference between descriptive statistics and inferential statistics?
What is a z-score, and what can it tell use about its corresponding raw score even if we do not hav access to the raw score?
Given the scores 23, 21, 19, 25, 21, 14, 20, 23, and 17 on a test, compute the mean, median, and mode. (You may use a calculator.)