Question

Frank is doing an experiment to find out how the amount of oxygen dissolved in water affects the growth of algae in a body of water. He dissolves different amounts of oxygen in ten otherwise identical samples of water.

What should Frank do next?
Place each sample of water in a freezer, and measure the temperature at which each freezes.

Add a pair of minnows to each sample of water, and measure the rate at which they reproduce.

Carefully bring each sample of water to a boil, and measure the temperature at which each boils.

Add equal amounts of algae to each sample of water, and measure the rates at which they grow.

Answer 1

Since the experiment is studying the growth of algae.  The only step that makes sense is putting in equal amounts of algae to each sample of water.  All of the other steps are testing different ideas.  For example placing the samples in a freezer to see what the freezing point is is testing how the amount of oxygen in water affects the freezing point of water.

Answer 2

As the algae die and begin its decomposition it consumes dissolved oxygen. As Frank is determining the effect of dissolved oxygen on algal growth, he should add equal amounts of algae to each sample of water, and measure the rates at which they grow, i.e. option D.

What is algae?

Algae is a group of aquatic mainly, photosynthetic, eukaryotic organism, belongs to the Protista kingdom.

When algae decompose it require oxygen that make deficiency of oxygen for the other aquatic organisms.

Frank is conducting experiment to determine the effect of oxygen on algal growth, he dissolved different amounts of oxygen in ten otherwise identical samples of water.

Next he must add equal amounts of algae to each sample of water, and measure the rates at which they grow.

Thus, the correct option is D.

For more details regarding algae, visit:

https://brainly.com/question/4289110

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