The subjects of a study by Borland et al. (A-35) were children in acute pain. Thirty-two children who presented at an emergency room were enrolled in the study. Each child used the visual analogue scale to rate pain on a scale from 0 to 100 mm. The mean pain score was 61.3 mm with a 95 percent confidence interval of 53.2 mm–69.4 mm. Which would be the appropriate reliability factor for the interval, z or t? Justify your choice. What is the precision of the estimate? The margin of error?