Answer: a. the amount of water
Independent variable can be defined as a variable which can be changed or manipulated in an experimental set up to record and observe it's effect on the dependent variable. A dependent variable is a variable which is dependent on the independent variable. The outcome of the dependent variable is the result of the experiment. A controlled variable is a variable which does not change in a reaction, and kept as a constant.
1. Here, in the given situation, the amount of water is an independent variable, as it can be manipulated or change in an experiment and it's impact on the growth of plant, which is a dependent variable needs to be observed.
2.Here, in the given, situation, the type of plant is a constant or control variable, as it is irrespective of the changes that occur in the dependent variable with respect to the independent variable.
Answer: A Tool that Shows Phenotypes of Genetically Related family Members, Are A pedigree.
Explanation:
The correct answer is - nitrogen and phosphorus.
The nitrogen and the phosphorus are the two substances that cause most of the eutrophication. It is good for the organisms that live in the water when these two substances are available as they are very important nutrients, but if the optimal amount is surpassed than it can be devastating. When there's high quantities of nitrogen and phosphorus in the water it makes it much more rich in nutrients that it should be. That kind of situation is the best for the algae, which start growing all over the place, quickly covering the water and becoming the dominant life form. As that happens, the organisms that use photosynthesis will die out because the Sun will be blocked, and the algae will also contribute to a big reduction of the oxygen in the water too. The end result being totally destroyed ecosystem that has been overtaken by algae.
