Hello! Please explain to me on how to get the answer to this problem.

RANDOM VARIABLE SITUATION: You are asked to buy milktea at B. T. H. Baler for your three friends for three consecutive days but with three flavor options only (Chocolate, Wintermelon, and Taro). Let X be equal to the number of Wintermelon (W) observed. What are the possible outcomes when you buy the flavor option for three days? Use tree diagram to represent the random variable. Note: 1. After constructing the diagram, write/list all the sample combinations in a sample space and determine the random variables. Use proper writing of sample spaces. 2. Construct the discrete probability distribution of random variable X