Based on a Random Sample of 13 Tire Changes, the Mean

question 108

Multiple Choice

Based on a random sample of 13 tire changes, the mean time to change a tire on a Boeing 777 has a mean of 59.5 minutes with a standard deviation of 8.4 minutes. For 10 tire changes on a Boeing 787, the mean time was 64.3 minutes with a standard deviation of 12.4 minutes. To test for equal variances in a two-tailed test at α = .10, the critical values are:

• A)3.73 and 0.228
• B)2.51 and 3.67
• C)3.07 and 0.398
• D)3.07 and 0.357

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Definitions:

Schwann Cells

Glial cells of the peripheral nervous system that wrap around axons, providing electrical insulation (myelination) and support for nerve regeneration.

Myelin Sheath

The fatty layer that surrounds and insulates nerve fibers, speeding up the transmission of nerve impulses.

Neurilemma

The outermost layer of a myelinated nerve fiber, which plays a crucial role in nerve regeneration and conduction.

Oligodendrocytes

A type of glial cell in the central nervous system responsible for producing and maintaining myelin sheaths around neurons.