If We Are Testing for the Difference Between the Means

question 2

Multiple Choice

If we are testing for the difference between the means of 2 independent populations presumes equal variances with samples of n₁ = 20 and n₂ = 20, the number of degrees of freedom is equal to

• A) 39.
• B) 38.
• C) 19.
• D) 18.

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Definitions:

Fovea

A small depression in the retina where visual acuity is highest.

Astigmatism Test Chart

A visual tool used to assess the presence and degree of astigmatism, featuring lines or patterns to help determine visual distortions.

Hyperopic

Referring to farsightedness, a common vision condition where distant objects can be seen clearly, but close ones do not come into proper focus.

Myopic

Nearsightedness; a condition in which close objects appear clearly but distant ones don't.