If Two Random Samples of Sizes 30 and 36 Are

question 106

Multiple Choice

If two random samples of sizes 30 and 36 are selected independently from two populations with means 78 and 85, and standard deviations 12 and 15, respectively, then the standard error of the difference and is equal to:

• A) 0.904
• B) 3.324
• C) 3.391
• D) 0.833

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Definitions:

Benthic Zone

refers to the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers.

Littoral Zone

The littoral zone is the area of a lake or ocean shore that is close to the shore, often characterized by shallow waters, where sunlight reaches the bottom allowing aquatic plants to grow.

Limnetic Zone

The open water area of a freshwater body, such as a lake, where sunlight penetrates deeply enough for photosynthesis to occur.

Decomposers

Organisms, such as bacteria and fungi, that break down dead organic material, recycling nutrients back into the ecosystem.