Student 2 is right.
<h3>Constant variables</h3>
In research investigations, some variables should be kept constant across various experimental groups in order for the outcome of the investigation to be valid.
For example, in order to test how flatworms respond to different environments, one variable that should be kept constant is the flatworms. The flatworms to be used must be of the same species, sex, age, etc.
The investigator can then go ahead to divide the flatworms into two or more groups and then subject them to different environments. Other variables should also be kept constant in order to determine the effects that are only specific to the different environments only.
More on constant variables can be found here: brainly.com/question/474060
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Answer:
O oceans, soils and forests
Explanation:
A carbon sink absorbs carbon from the environment. They do not release carbon to the environment.
The atmosphere is a good carbon source since it contains a significant amount of carbon dioxide gas.
- Carbon is found in the ocean in dissolved form.
- Soils are also good carbon sinks.
- Forest trees use carbon for their life processes
- One very integral process where carbon is used up is at photosynthesis.
- The carbon is used to make food materials.
Answer:
Explanation:
The circulatory system consists of typically two organs these are the heart which also belong to the cardiovascular system and the lungs which also belong to the respiratory system these are connected to the arteries, veins and other blood vessels. The lungs receives the oxygen which diffuse oxygen into the blood vessels which transports the oxygenated blood to the heart which is pumped and circulated by the heart to all the parts of the body.
I believe the answer is true but I couldn't quite understand the question.
Hope this helps.
