The Three-Dimensional Shape of __________ Is Set by the Average

question 31

Multiple Choice

The three-dimensional shape of __________ is set by the average velocities of the stars along each of the three axes.

• A) spiral galaxies
• B) only elliptical galaxies
• C) spiral bulges
• D) elliptical galaxies and spiral bulges
• E) quasars

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Definitions:

Pretest-Posttest

A research design that measures the effect of an intervention by comparing conditions before and after the intervention is applied.

Posttest-Only

A research design where measures are taken only after the experimental manipulation, without a pretest comparison.

Mortality

The loss of subjects who decide to leave an experiment. Mortality is a threat to internal validity when the mortality rate is related to the nature of the experimental manipulation.

Experimental Design

A research design used to test hypotheses and establish cause-effect relationships by manipulating one or more independent variables and observing the effect on dependent variables.