. Other Continuous Distributions: Uniform and Exponential 253 a social network would follow a uniform distribution be- tween 0 and 1 (Social Networks, 2010). a. On average, what is the density of a randomly selected social network? b. What is the probability that the randomly selected net- work has a density higher than .7? c. Consider a social network with only 2 members. Explain why the uniform model would not be a good approximation for the distribution of network density. 4.146 Boeing 787 Dreamliner. An assessment of the new Boeing 787 "Dreamliner" airplane was published in the Journal of Case Research in Business and Economics (December 2014). Boeing planned to build and deliver 3,500 of these aircraft within the first 20 years of the 787 program. The researchers used simulation to estimate the number of annual deliveries of 787 airplanes (expressed as a percent- age of total Boeing aircraft deliveries during the year). In the fifth year of the program, deliveries were uniformly distributed over the range 2.5% to 5.5%. Assuming the 25. simulated results are accurate, what is the probability that le the number of Boeing 787s built and delivered in the fifth m year of the program exceeds 4% of the total Boeing air- craft deliveries during the year? ire 4.147 Soft-drink dispenser. The manager of a local soft-drink bottling company believes that when a new beverage- ax dispensing machine is set to dispense 7 ounces, it in fact dispenses an amount x at random anywhere between 6.5 ol- and 7.5 ounces inclusive. Suppose x has a uniform probabil- it x ity distribution. oxi- a. Is the amount dispensed by the beverage machine a dis- ams crete or a continuous random variable? Explain