A National Manufacturer of Ball Bearings Is Experimenting with Two $\neq$

question 86

Multiple Choice

A national manufacturer of ball bearings is experimenting with two different processes for producing precision ball bearings. It is important that the diameters be as close as possible to an industry standard. The output from each process is sampled and the average error from the industry standard is calculated. The results are presented below.
The researcher is interested in determining whether there is evidence that the two processes yield different average errors. Assume that the population standard deviations are equal. What is the alternate hypothesis?

• A) H₀: µ_A = µ_B
• B) H₀: µ_A \(\neq\) µ_B
• C) H₀: µ_A \(\le\) µ_B
• D) H₀: µ_A > µ_B

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Definitions:

Interleukin 2

A type of cytokine produced by T-cells that plays a critical role in the regulation of immune responses, including the activation and proliferation of lymphocytes.

Suppressor T Cell

Subset of T lymphocytes that decreases the activity of B cells and T cells.

Cytokines

Small proteins released by cells, especially immune cells, that have a specific effect on the interactions and communications between cells.

Secondary Response

Immune response that occurs when the immune system is exposed to an antigen against which it has already produced a primary response; also called memory response.