Eliza earns $400 per week plus $15 for each new customer she signs up. Let c represent the number of new customers Eliza signs up. Write
an expression that shows how much she earns in a week.

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.