Online customer service is a key element to successful online retailing. According to a marketing survey, 37.5% of online customers take advantage of the online customer service. Random samples of 200 customers are selected. 1. Referring to Data 2, the population mean of all possible sample proportions is ________. 2. Referring to Data 2, the standard error of all possible sample proportions is ________. 3. Referring to Data 2, ________ % of the samples are likely to have between 35% and 40% who take advantage of online customer service. 4. Referring to Data 2, ________ % of the samples are likely to have less than 37.5% who take advantage of online customer service. 5. Referring to Data 2, 90% of the samples proportions symmetrically around the population proportion will have between ________ % and ________ % of the customers who take advantage of online customer service. 6. Find the standard error using fpc for Data 2 from a population of 1000.