A researcher is interested in exploring the relationship between calcium intake and weight loss. Two different groups, each with 28 dieters, are chosen for the study. Group A is required to follow a specific diet and exercise regimen, and also take a 500-mg supplement of calcium each day. Group B is required to follow the same diet and exercise regimen, but with no supplemental calcium. After six months on the program, the members of group A had lost a mean of 11.1 pounds with a standard deviation of 2.7 pounds. The members of group B had lost a mean of 10.5 pounds with a standard deviation of 1.7 pounds during the same time period. Assume that the population variances are not the same. Construct a 90% confidence interval to estimate the true difference between the mean amounts of weight lost by dieters who supplement with calcium and those who do not. Let population 1 be the amount of weight lost by Group A, who took a 500-mg supplement of calcium each day, and let population 2 be the amount of weight lost by group B, who did not take a calcium supplement. Round the endpoints of the interval to one decimal place, if necessary.