You may need to use the appropriate appendix table or technology to answer this question. A comparative study of organic and conventionally grown produce was checked for the presence of E. coli. Results are summarized below. Sample Size E. coli Prevalence 2 Organic 200 Conventional 520 21 Is there a significant difference in the proportion of E. coli in organic vs. conventionally grown produce? Test at a = 0.10. (Let d = Organic - Conventional.) (a) Formulate the hypotheses. Hoi P1 P2-0 Ha P1 P20 Ho: P1-P 0 Ha: P1 P2 = 0 Ho P1 P250 HP1 P2 0 Ho P1 P20 Ha: P-P 50 0 Ho: P: P20 HP1 P20 (b) What is the value of the test statistic? (Round your answer to three decimal places.)