Composite Water Samples The Fairfield County Department of Public Health tests water for contamination due to the presence of E. coli (Escherichia coli) bacteria. To reduce laboratory costs, water samples from five public swimming areas are combined for one test, and further testing is done only if the combined sample tests positive. Based on past results, there is a 0.005 probability of finding E. coli bacteria in a public swimming area. Find the probability that a combined sample from five public swimming areas will reveal the presence of E. coli bacteria. Is that probability low enough so that further testing of the individual samples is rarely necessary?