Mid-West Publishing Company publishes college textbooks. The company operates an 800 telephone number whereby potential adopters can ask questions about forthcoming texts, request examination copies of texts, and place orders. Currently, two extension lines are used, with two representatives handling the telephone inquiries. Calls occurring when both extension lines are being used receive a busy signal; no waiting is allowed. Each representative can accommodate an average of 11 calls per hour. The arrival rate is 22 calls per hour. a. How many extension lines should be used if the company wants to handle 90% of the calls immediately? b. What is the probability that a call will receive a busy signal if your recommendation in part (a) is used? If required, round your answer to four decimal places. c. What number of calls, in decimal form, receive a busy signal for the current telephone system with two extension lines? If required, round your answer to four decimal places.

For the three-part question that follows, provide your answer to each question in the given workspace. Identify each part with a coordinating response. Be sure to clearly label each part of your response as Part A, Part B, and Part C.Part A: What is the term for a generalization made about a population using the data from a sample?Part B: Name one challenge that may occur when using a sample to draw a conclusion about a population.Part C: A researcher collects data about the annual salary of employees who work in the information technology field. It would be difficult to survey all employees, so a sample of the population is surveyed. The data is recorded below. Use the table to write one conclusion that can be drawn. Explain why this conclusion is valid. Salary Range (Per Year) Number of Employees $50,000-$59,999 147 $60,000-$69,999 159 $70,000-$79,999 225 $80,000-$89,999 27

Kara, Sammy, Liz, and Mark each took many samples from the same population of students. The number of students in each sample is shown in the table. Which person's sampling distribution was most likely to closely approximate the population distribution? Person taking sample Number of students in each sample Kara 14 Sammy 83 Liz 46 Mark 65

Use the following results from a test for marijuana use, which is provided by a certain drug testing company. Among 140 subjects with positive test results, there are 30 false positive results. Among 159 negative results, there are 3 false negative results. Complete parts (a) through (c). (Hint: Construct a table.) a. How many subjects were included in the study? The total number of subjects in the study was ...