The following are zinc concentrations (in mg/ml) in the blood for two groups of rats. Group A received a dietary supplement of calcium, and group B did not. Researchers are interested in variations in zinc level as a side effect of dietary supplementation of calcium.
Group A: 1:31 1:45 1:12 1:16 1:30 1:50 1:20 1:22 1:42 1:14 1:23 1:59 1:11 1:10 1:53 1:52 1:17 1:49 1:62 1:29
Group B: 1:13 1:71 1:39 1:15 1:33 1:00 1:03 1:68 1:76 1:55 1:34 1:47 1:74 1:74 1:19 1:15 1:20 1:59 1:47
(a) Make a back-to-back stem-and-leaf diagram (by hand) for these measurements.
(b) Use the computer to draw side-by-side box plots.