Titanium alloys have very high hardness. Adding small amounts of copper tends to improve their properties, such ashardness. In order to evaluate the effect of copper addition on hardness of titanium alloys, 10 random casts with 5%copper were made in an argon-arc melting furnace. The Rockwell hardness was determined for each of the casts. Then,the casts were subjected to high temperature (HT) and hardness was determined again in the second row. Assumehardness follows a normal distribution. Use the data below to answer the next three questions.248 246 245 251 248 250 247 246 243 244HARD5HARD5HT 250 247 246 251 251 253 248 246 249 247(a) Do the data provide evidence that high temperature increases the hardness of 5% copper alloys, on average? What isthe distribution of the test statistic under the null hypothesis and the exact p-value?O t-distribution with df = 18; p-value = 0.0862O t-distribution with df = 9; p-value = 0.00712O t-distribution with df = 9; p-value = 0.00356O t-distribution with df = 18; p-value = 0.9569O t-distribution with df = 18; p-value = 0.0431(b) What is the BEST CORRESPONDING 95% confidence interval or bound for Hd, where d = xH5 - XH5HT?О (3.306, о0)O (-3.306, -0.694)O (-00, -0.942)O (-3.058, ∞)О (00, -0.694)

Test is that whether high temperature increases the hardness of 5% copper alloys.

Answered: (a) Do the data provide evidence that…

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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