Let u = {1,2,3,4,5}, a = {1,2,3} and b = {2,3,4}. 1. describe the relations between each of these sets. use your own words. 2. describe the relations between these sets using mathematical notation (statements! ) 3. we wish to construct a new set s = an b. what is s? (hint: aºis the complement of a). 4. draw a venn diagram highlighting s. 5. how many elements does p ({u}) have? explain why.

In a survey of 1015 adults, a polling agency asked, "when you retire, do you think you will have enough money to live comfortably or not. of the 1015 surveyed, 534 stated that they were worried about having enough money to live comfortably in retirement. construct a 90% confidence interval for the proportion of adults who are worried about having enough money to live comfortably in retirement.