Duckweed Is a Small,flowering Plant That Floats at the Water's

question 55

Multiple Choice

Duckweed is a small,flowering plant that floats at the water's surface.It tends to grow best when nutrient levels are high.When duckweed is abundant,it forms tight mats that cover the surface of ponds and lakes.Consider a situation in which spring storms bring an influx of water and nutrients into a small 4-acre pond,and duckweed populations suddenly explode.Duckweed covers nearly all the surface of the pond,but is regularly washed over the spillway only to be replaced rapidly by the growth of new duckweed plants.
-While the duckweed continues to cover the water's surface of this pond undergoing eutrophication,it is most likely that the water clarity will

• A)be high and the growth of submerged aquatic vegetation will increase.
• B)be high but the growth of submerged aquatic vegetation will decrease.
• C)decrease and the growth of submerged aquatic vegetation will increase.
• D)decrease and the growth of submerged aquatic vegetation will decrease.

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Definitions:

Normal Distribution

A bell-shaped distribution curve which is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean.

Variance

A measure of the dispersion indicating how far individual numbers are from the mean.

Chi-squared Distribution

A statistical tool used to compare observed data with data we would expect to obtain according to a specific hypothesis.

Sample

A subset of individuals or units from a larger population used to estimate characteristics of the whole population.