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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Suppose that for a random sample of 250 firms that revalued their fixed assets, the mean ratio of debt to tangible assets was 0.629, and the sample standard deviation was 0.177. For an independent random sample of 450 firms that did not revalue their fixed assets, the mean ratio of debt to tangible assets was 0.599, and the sample standard deviation was 0.163. Assuming that the population distributions are normal with equal variances, find a 95% confidence interval for the difference between the two population means. E Click the icon to view a table of upper critical values of Student's t distribution. A 95% confidence interval for the difference between the two population means is (Round to four decimal places as needed.)
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H3.
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