Identify two uses of Poisson distributions.

Emissions of nitrogen oxides, which are major constituents of smog, can be modeled using a normal distribution. Let x denote the amount of this pollutant emitted (in parts per billion) by a randomly selected vehicle. Suppose the distribution of x can be described by a normal distribution with  ? = 1.8  and  ? = 0.4.  A city wants to offer some sort of incentive to get the worst polluters off the road. What emission levels constitute the worst 10% of the vehicles? (Round your answer to four decimal places.)

A certain brokerage house wants to estimate the mean daily return on a certain stock. A random sample of 10 days yields the following return percentages. -2.1, -1.77, 0.35 , 2.08, 1.98, 0.08, –2.89,-2.79, -2.48,2.56 Send data to calculator Send data to Excel If we assume that the returns are normally distributed, find a 99% confidence interval for the mean daily return on this stock. Give the lower limit and upper limit of the 99% confidence interval. Carry your intermediàte computations to at least three decimal places. Round your answers to one decimal place. (If necessary, consult a list of formulas.) Lower ? limit: Upper limit: O O

Which of the following is least likely to be normally distributed? (Hint: Think of a graph of each of these variables to try to determine which is most likely to be skewed.) height of females at CSUF shoe size of females at CSUF IQ scores of high school seniors high school GPA of entering freshman at Harvard