Two styles of water filter were being considered for drinking water in remote rural villages: one with a thick layer of sand and one with a thin layer of sand. It was predicted that the thicker filter would be most effective at reducing E. coli counts (number of bacteria per 100 mL water). See water filters.jmp.

a. Does this dataset meet the t robustness criteria? Yeso and explain your reasoning.

b. Write a set of hypotheses for this analysis.

c. E. coli in drinking water can cause illness and sometimes even death among the very young, very old, or immunocompromised persons. Would the 1%, 5%, or 10% significance level be most appropriate here? Explain.

d. Complete steps 3-7 of the hypothesis test.

E coli (count ... 18 o 77 4 263 75 5 0 Filter type 1 thick 2 thick 3 thick 4 thick 5 thick 6 thick 7 thick 8 thick 9 thick 10 thick 11 thick 12 thick 13 thick 14 thick 15 thin 16 thin 17 thin 18 thin 19 thin 6.7 33 50 10 0 2 200 170 0 33 E coli (count ... 18 o 77 4 263 75 5 0 Filter type 1 thick 2 thick 3 thick 4 thick 5 thick 6 thick 7 thick 8 thick 9 thick 10 thick 11 thick 12 thick 13 thick 14 thick 15 thin 16 thin 17 thin 18 thin 19 thin 6.7 33 50 10 0 2 200 170 0 33