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Consider the proof. given: segment ab is parallel to line de. prove: what is the missing statement in step 5?

Express the following as a function of a single angle. cos(60) cos(-20) - sin(60) sin(-20)

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.