Researchers are designing a case-control study to examine the association between taking Vitamin D supplements and the risk of dementia. The researchers would like to have 80% power to detect a minimum odds ratio (OR) of 2.00, at an alpha level of 0.05 using a chi-square test. They estimate the proportion of controls exposed to vitamin D supplements would be approximately 30%. Assume that both groups will be the same size.

(i) Assuming equal sized groups, the number of participants per groupneeded to achieve 80% power would be: per group (ii) What level of power (as a percentage, with no decimal places) would be achieved if there were 180 patients per group: % (iii)If the sample size were 180 patients per group, with the original desired power of 80%, what would be the minimum detectable OR (assuming exposure increases the odds of the outcome) - provide your answer as a numeric value to 2 decimal places: