An Environmental Scientist Obtains a Sample of Water from an Irrigation

question 42

Multiple Choice

An environmental scientist obtains a sample of water from an irrigation canal that contains a certain type of bacteria at a concentration of 2 per milliliter. Find the standard deviation of the number of Bacteria in a 4-milliliter sample.

• A) 8
• B) 1.4
• C) 2.8
• D) 2

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Definitions:

Carryover Effects

A phenomenon in repeated measures designs where the effect of previous condition(s) carries over to influence performance in subsequent condition(s).

AB Design

A basic experimental design consisting of a control phase (A) followed by a treatment phase (B), used primarily in behavior analysis to assess the effect of a treatment or intervention.

Randomized AB Design

An experimental design involving random assignment to two groups, A (control) and B (treatment), to examine the effect of a variable.

ABAB Design

Another name for Reversal Design, illustrating the sequence of observational and intervention phases: A (baseline) followed by B (intervention), another A (withdrawal of intervention), and final B (re-introduction of intervention).