An environmental agency worries that many cars may be violating clean air emission standards. The agency hopes to check a sample of vehicles in order to estimate that percentage with a margin of error of 3% and 99% confidence. To gauge the size of the problem, the agency first picks 60 cars and finds 15 with faulty emissions. How many should be sampled for a full investigation?

How many $20 bills do you need to have to make $280

If f(x) = x+8 and g(x) = 4x- 3, find (f+g)(x)

In one day there are too high tides into low tides and equally spaced intervals the high tide is observed to be 6 feet above the average sea level after six hours passed a low tide occurs at 6 feet below the average sea level in this task you will model this occurrence using a trigonometric function by using x as a measurement of time assume the first high tide occurs at x=0. a. what are the independent and dependent variables? b. determine these key features of the function that models the tide: 1.amplitude 2.period 3.frequency 4.midline 5.vertical shift 6.phase shift c. create a trigonometric function that models the ocean tide for a period of 12 hours. d. what is the height of the tide after 93 hours?