The Engineering Department at Sims Software Inc. recently developed two chemical solutions designed to increase the usable life of computer disks. A sample of disks treated with the first solution lasted 86, 78, 66, 83, 84, 81, 84, 109, 65, and 102 hours. Those treated with the second solution lasted 91, 71, 75, 76, 87, 79, 73, 76, 79, 78, 87, 90, 76, and 72 hours. Assume the population standard deviations are not the same.

At the .10 significance level, can we conclude that there is a difference in the length of time the two types of treatment lasted?

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1.	The degrees of freedom is . (Round down your answer to nearest whole number.)

2.	Reject H0 if t < or t > (Negative amounts should be indicated by a minus sign. Round your answers to 3 decimal places.).

3.	The test statistic is . (Round your answer to 2 decimal places.)

4.

Decision: