What causes alteration of plant debris that make coal?
fine debris emitted as a byproduct of coal combustion. coal, oil, or natural gas. Fossil fuels formed from the remains of ancient plants and animals. device used for heating by burning a fuel, such as wood or coal.
A control group is sort of the normal group. The group you aren't changing or messing with. It is to show what the species/experiment acts like on its own in response to something without you having to change it at all.
With an experimental group, you are changing something about the subject before putting it in the conditions it will need to respond to.
I don't entirely understand, but I know the control group is constant, unchanging. It sort of helps with distinguishing things. I have examples of experiments if that will help you understand what a control group is to answer the question. I also have a The Death Cure example if you have seen or read the book. I hope you do not fail this assignment, but even if I did not answer with an answer you were looking for, it could have helped you answer the question on your own.
I saw somewhere a similar question, though I was given the answer choices. If this is the answer you are looking for: variable(s).
Control groups don't use variables because you aren't changing them.
Scientific advancement has increased food safety by the use of preservatives, refrigeration, better packaging, labels with expiration dates...that's a good many right there!
Nuclear power is a clean and efficient way of boiling water to make steam, which turns turbines to produce electricity. Nuclear power plants use low-enriched uranium fuel to produce electricity through a process called fission—the splitting of uranium atoms in a nuclear reactor.