Emma's On-the-Go, a large convenience store that makes a good deal of money from magazine sales, has three possible locations In the store for Its magazine rack: In the front of the store (to attract "Impulse buying" by all customers), on the left-hand side of the store (to attract teenagers who are on that side of the store looking at the candy and soda), and In the back of the store (to attract the adults searching through the alcohol cases). The manager at Emma's experiments over the course of several months by rotating the magazine rack among the three locations, choosing a sample of 43 days at each location. Each day, the manager records the amount of money brought In from the sale of magazines. Below are the sample mean daily sales (In dollars) for each of the locations, as well as the sample variances: Sample Sample Group Sample size mean variance Front 219.8 402.7 Laft-hand side 212.3 480.6 Right-hand 211.8 404.1 side Assume that the populations of daily sales from which the above samples were drawn are approximately normally distributed and that each has the same mean and the same variance. Answer the following, carrying your Intermediate computations to at least three decimal places and rounding your responses to at least one decimal place. (a) Give an estimate of this common population variance by pooling the sample variances given. (b) Give an estimate of this common population variance based on the variance of the sample means given. X