The health of fish depends on the amount of oxygen dissolved in the water. A dissolved oxygen (DO) concentration between 6 parts per million and 8 parts per million is best for fish health. A DO concentration greater than 1 part per million is necessary for fish survival. A student's fish tank contains fish, green plants, and 3800 grams of fish-tank water with 2.7 × 10 -2 gram of dissolved oxygen. Write a statement using this information that tells why the DO concentration in the water is or is not healthy for fish.

The tank´s  Dissolved Oxygen Concentration is healthy for the fish because it is 7,1 parts per million. (Inside the rule between 6 and 8 parts per million)

Explanation:

When Calculating parts per million, we must know "ppm" means "mg/kg". This is a simply conversion factors operation. In this case, 2,7x 10-2 grams of Dissolved oxygen must be converted into miligrams, multiplying per 1000 and 3800grams of water must be converted into kilograms, multiplying per 1000, as we can see in the image below.

the only liquid elements at standard temperature and pressure are bromine (br) and mercury (hg). although, elements caesium (cs), rubidium (rb), francium (fr) and gallium (ga) become liquid at or just above room temperature.

explanation:

the old alchemists made significant contributions to science even though there starting premises were off a bit. their conclusions after failure would steer them into better directions for investigation. science is no more than close observation and the initial mistakes result in rethinking and retrying experiments.