Construct a spreadsheet simulation in which each trial consists of rolling of four dice. That is, there are four random variables each with an outcome of 1, 2, 3, 4, 5, or 6. For each trial, record the value of the first dice, the sum of the first two dice, the sum of the first three dice, and the sum of the first four dice. Using the FREQUENCY command, create a frequency distribution for each of these four computations on a separate plot. What phenonemon do you observe?