Two Independent Samples of Sizes 40 and 50 Are Randomly

question 29

Multiple Choice

Two independent samples of sizes 40 and 50 are randomly selected from two populations to test the difference between the population means . Assume the population variances are known. The sampling distribution of the sample mean difference is:

• A) normally distributed.
• B) approximately normal.
• C) Student t-distributed with 88 degrees of freedom.
• D) None of these choices.

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