Please do only number 2 and show work without using square roots. The answer is A=8 and B=4.

Normal Distribution 1-11 1) Compare Rock Collections- For Each: a) Graph Histograms b) Range c}A1-itbmec Mean: d) Variance = sigtmt2 e)standa.1d deviation f) Using ae; Compare the three groups 2} Set consisting of: { 3, A, 6, B, 13} has a mean of 6.8 and a standard deviation of 12.56. Find A and B given thatA > B. 3} A normal distribution has a mean of 56 and a standard deviation of 8. Find the probability that a randomly selected xvalue is in the given interval. a. between 40 and 64 b. between 32 and 40 c. between 56 and 64 d. at most 56 e. at least 1'2 f. at most 64 4} The developing times of photographic prints are normally distributed with a mean of 15.4 seconds and a standard deviation of 0.48 seoond. a. What is the probability that the developing time of a print will be at least 16.36 seconds? b. What is the probability that the developing time of a print will be between 13.96 seconds and 15.88 seconds? 5} A college-entrance exam is designed so that scores are normally distributed with a mean of 500 and a standard deviation of 100. a] What percent of exam scores are between 400 and 600? b] What is the probability that a randomly chosen exam score is above 600? c] What is the probability that a randomly chosen exam score is less than 300 or greater than TDEI? d] What is the probability that a randomly chosen exam score is above 300? 6} Flight 202's arrival time is normally distributed with a mean arrival time of 4:30pm. and a standard deviation of 15 minutes. Find the probability that a randomly chosen arrival time is within the given time period. a} After 4:45 pm. hi between 4:15 pm. and 5:00 pm. c} between 3:45 pm. and 4:30 pm. d} by 4:45 pm. 1' I\" a' 7} 0n the driving range, Tiger Woods practices his swing with a particular club by hitting many, many balls. When Tiger hits his driver, the distance the ball travels follows a Normal distribution with mean 304 yards and standard deviation 8 yards. a] What percent of Tiger's drives travel at least 290 yards? b) What percent of Tiger's drives travel between 305 and 325 yards? c) What distance would a ball have to travel to be at the 80th percentile of Tiger Woods's drive lengths? If it's a normal distribution the z score = 8} High levels of cholesterol in the blood increase the risk of heart disease. For 14-year-old boys, the distribution of blood cholesterol is approximately Normal with mean |.l. = 170 milligrams of cholesterol per deciliter of blood {mg/dll and standard deviation o= 30 mgfdl a] Cholesterol levels above 240 mgfdl may require medical attention. What percent of 14-year-old boys have more than 240 mgfdl of cholesterol? b) What percent of 14-year-old boys have blood cholesterol between 200 and 240 mgfdl? c) What is the 25'11 percentile of the distribution of blood cholesterol? 9} The weekly income of a bakery is normally distributed with a mean of 56,100. If 85% of the time the weekly income exceeds $6,000 what is the standard deviation? 10} The arrival times of buses at a depot are normally distributed with standard deviation of five minutes. If 10% of the buses arrive before 3:55 PM , find the mean arrival of the buses at the depot 11} a} Find the mean and standard deviation of a normally distributed random variable X, given that P{X > 80} = 0.1 and P{X