I need help with question b in the first picture & c in the last two, the other ones are solved. Thanks

A survey looked at how long it takes a typical company to recoup an investment in research. The survey determined that 32% of the corporations took six months or less to recoup their investment. The data table below shows a sample of the time, in months, it might have taken 20 corporations to recoup their investment. Complete parts a through c. 8.5 5.5 7.0 7.5 9.0 8.0 7.5 10.0 9.0 8.0D 9.0 3.5 7.5 8.0 4.5 10.5 4.0 11.5 7.5 7.5 <:> a. Determine the number of corporations that recovered their investement in research in six months or less. There were 4 corporations that recovered their investment in research in six months or less. b. Calculate the probability of obtaining at most the number of corporations that you determined in part a if the percent of those recovering their investment is as indicated by the survey. The probability is 0.1827 . (Round to four decimal places as needed.) c. Using the distribution from the previous part, determine the 70th percentile of the number of the 20 corporations that recovered their investment in research in six months or less . (Hint: The 70th percentile corresponds to the value such that 70% of the data is as small or smaller.) The percentile is :|. (Type a whole number.) A coffee shop has entered into an agreement with a publisher to begin selling a food and beverage magazine on a trial basis. The magazine retails for $3.95 in other stores. The coffee shop bought it for $1.95 and sold it for $3.49. During the trial period, the coffee shop placed 10 copies of the magazine in each of 25 stores throughout the country. The accompanying table contains the number of magazines sold in each of the stores. Complete parts a through c. a Click on the icon to view the data table. \\Iypu "\"55an u: uGUIIIIaIO.' Number Sold, x Frequency P(x) 0 1 0.04 0 0 2 .08 2 .08 5 0.2 7 .28 5 0.2 2 .08 0 0 1 .04 0 0 mmthNl _; O b. Calculate the expected prot from the sale of these 10 magazines. $- (Round to two decimal places as needed.) b. Calculate the expected value and standard deviation for the time until the covers became unserviceable. E(x) = 18.89 (Type an integer or a decimal.) ox = 1.886 (Round to three decimal places as needed.) c. The quality-control department thinks that among those covers, the majority last longer than 19 months. Produce the relevant statistic to verify this assumption. For the majority of the covers to last longer than 19 months. P(x219) would have to be at least 0.5. Here. P(x 219 = Cl and the quality-control department is correct