Problem 2.An article in Fire Technology investigated two different foam-expanding agents that can be usedin the nozzles of fire-refighting spray equipment. A random sample of five observations with anaqueous film-forming foam (AFFF) had a sample mean of 4.1 and a standard deviation of 0.6. Arandom sample of five observations with alcohol-type concentrates (ATC) had a sample mean of6.6 and a standard deviation 0.8.a. Can you draw any conclusions about differences in mean foam expansion? Use a = 0.05.Assume that both populations are well represented by normal distributions with the samestandard deviations. Find the value of the test statistic. Suppose that the null hypothesis isHo: M-₂A=0. What is your conclusion about differences in mean foam expansion?b. Find a 95% confidence interval on the difference in mean foam expansion of these twoagents.Problem 3.A random sample of 1900 adult women indicated that 941 of them asked for medical assistancelast time they felt sick. The same sized sample of men indicated that 893 of them asked formedical assistance.Use the z-values rounded to three decimal places to obtain the answers.a. Is it reasonable to conclude that women ask for medical assistance more often than men?Use a = 0.05. Find the P-value for this test.b. Construct a 95% confidence interval for the difference in the proportion of women andproportion of men who seek medical assistance.

As per the Bartleby guildlines we have to solve first question and rest can be reposted.... Problem…

Answered: Problem 2. An article in Fire…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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The human resources director of a large company recently asked her staff to conduct a study of the airline miles traveled by executives of the company during the most recent calendar year. The analyst assigned to the project randomly sampled 25 male executives and 25 female executives. Of particular interest to the HR director is whether males have greater variability in miles flown than females. The statistics available below were computed from the samples. Based on these data, what should the HR director conclude if an alpha level equal to 0.01 is used? LOADING... Click the icon to view the statistics about the number of miles flown. Males Females Mean Miles 73,262 66,888 St. Deviation Miles 2,568 1,539 Sample Size 25 25 Let sample 1 be males and sample 2 be females. What are the null and alternative hypotheses? A. H0: σ21=σ22 HA: σ21≠σ22 B. H0: σ21≤σ22 HA: σ21>σ22 C. H0: σ21≥σ22 HA:…
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