1. If the reliability level is 90%, the variable of interest represents 25% of the population and the accepted margin of error is 4%. Determine the sample size: a. When the population size is unknown b. if the population size is 60 units. 2. Of a product X, 15,000 units are made per month in factory 1, out of a total of 30,000 that are made in all the corporation's factories. Assume that the confidence level is 95% and the accepted margin of error is 0.05. Determine the sample size. 3. Determine the sample size of (2) above assuming that the sample will be taken from a single day production of 500 at factory 1. 4.Determine the sample size to survey the customers of a store in a shopping center if there are 300 customers out of 5,000 in all the stores of the corporation. Assume that the confidence level is 95% and the accepted margin of error is 0.05. 5.Determine the size of the sample from the previous exercise (4) assuming that the sample of customers is taken from one of the departments of the store where there are a total of 100 customers.