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Determine if the graph is symmetric about the x-axis, the y-axis, or the origin. r = -2 + 3 cos θ (5 points)

A railroad tunnel is shaped like a semiellipse, as shown below.   The height of the tunnel at the center is 54 ft, and the vertical clearance must be 18 ft at a point 8 ft from the center. Find an equation for the ellipse. (5 points)

(05.05 LC)  A random sample has been taken from a population. A statistician, using this sample, needs to decide whether to construct a 95% confidence interval for the population mean or a 99% confidence interval for the population mean. How will these intervals differ? (4 points)

Find the standard form of the equation of the parabola with a focus at (0, -10) and a directrix at y = 10. (5 points)

Will bacteria living in hot springs have more saturated or unsaturated fatty acids?  Give reason for your answer.    

(05.01 LC)  A study of pet owners included 752 owners who were chosen at random. Of these pet owners, 63% said they had spayed or neutered their pets. Vet records show that only 39% of pet owners spay or neuter their pets. Identify the statistic and the parameter. (4 points)

Find the rectangular coordinates of the point with the polar coordinates. (5 points)

(05.04 MC)  A zoning board in Pine County is interested in estimating the proportion of its residents in favor of larger school zones in that county. A random sample of Pine County residents was selected. All the selected residents were asked, “Are you in favor of larger school zones in your county?” A 95% confidence interval for the proportion of residents in favor of larger school zones in that county was calculated to be 0.48 ± 0.02. Which of the following statements is correct? (4 points)

What type of microscopy provides a three-dimensional view of the surface of an object?

(05.01 LC)  A study of fishermen included 812 anglers who were chosen at random. Of these anglers, 59% said they use live bait. Bait shop owners show that only 41% of anglers use live bait. Identify the statistic and the parameter. (4 points)