Three different washing solutions are being compared to study their effectiveness in retarding bacteria growth in 5-gallon milk containers. The analysis is done in a laboratory, and only three trials can be run on any day. Because days could represent a potential source of variability, the experiment decides to use a randomized block design. Observations are taken for four days, and the data are shown here.

Days Solutions Yi. 1 2 3 13 22 18 39 16 24 17 44 5 4 1 22 Y.j