Two Samples Are Selected at Random from Two Independent Normally $\bar { X } _ { 1 } - \bar { X } _ { 2 }$

question 9

Multiple Choice

Two samples are selected at random from two independent normally distributed populations. Sample 1 has 49 observations and has a mean of 10 and a standard deviation of 5. Sample 2 has 36 observations and has a mean of 12 and a standard deviation of 3. The standard error of the sampling distribution of the sample mean difference, $\bar { X } _ { 1 } - \bar { X } _ { 2 }$ , is:

• A) 0.1853.
• B) 0.7602.
• C) 0.7331.
• D) 0.8719.

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Definitions:

Genetic Limits

The inherent boundaries or constraints on an organism's traits (such as height or intelligence) determined by its genetic makeup.

Genotype-Environment Correlation

Tendency of certain genetic and environmental influences to reinforce each other; may be passive, reactive (evocative), or active. Also called genotype-environment covariance.

Prenatal Stage

The period of development occurring before birth, from conception to the onset of labor, crucial for healthy fetal development.

Zygote

is the initial cell formed when a new organism is produced by sexual reproduction, resulting from the union of an egg and a sperm cell.