A study on students drinking habits wants to determine the true average number of alcoholic drinks all UF underclassmen students have in a one week period. We know from preliminary studies that the standard deviation is around 2.8. How many students should be sampled to be within 1.5 drink of population mean with 90% probability

70 points ! pls 2. given the following two sets of data what is the union of the two sets and what is the intersection of the two sets. set a = {1, 2, 3, 4, 5, 6, 7, 8, 9} set b = {2, 4, 6, 8, 10, 12, 14} 3. given a regular deck of cards. describe a way of pulling cards that would create a dependent event and then one that would create an independent event. 4. what is the probability of drawing a red card and then drawing a spade without replacing the card that was drawn first?