Using coal for fuel releases pollution into the atmosphere. why do people continue to use coal if it causes pollution.
a. using more coal reduces the amount of pollution from using oil.
b. using coal is relatively inexpensive.
c. mining coal scientists uncover fossils.
d. using coal, instead of wood from trees, conserve trees.

Hello. You haven't shown which project this question is referring to, but I can help you by showing the meaning of each of these terms.

The independent variable is one that does not need to be influenced by any factor to be measured and that acts on top of elements to cause a result to happen. An example of this can be seen in an experiment that wants to analyze the influence of organic fertilizer on the growth of transgenic tomato plants. Organic fertilizer is influencing a result, so it is the independent variable.

The dependent variable is one that needs to be measured through the influence of the independent variable. This variable suffers the action of the independent variable so that it can generate a result. In the example used above, we can say that the dependent variable is the growth of transangenco tomato plants, since this growth depends on the application of organic fertilizer.

Controlled variables are elements of the experiment that remain constant throughout the experiment. They serve to give consistency and stability to the results. Still using as an example the experiment that tests the influence of organic fertilizer on the growth of transgenic tomatoes, we can mention the controlled variables such as: the tomato seeds, the water used to irrigate the plants, the size of the pots, the amount of error, the greenhouse where the plants are being harvested, among others.

The control group is the element of the experiment that does not receive the factor being tested. This element will be used to compare your result with the experimental groups and see if there are any differences between them. An example of a control group will be the pots that will not receive organic fertilizer, but will receive the seeds of transgenic tomatoes.

The experimental group is the element that receives the factor that is being tested in the experiment. It is the main part of the experiment, because it will be responsible for showing the real results of what is being tested. An example of this is the pots that will receive the organic fertilizer and the seeds of transgenic tomatoes.

The large sample size refers to the number of elements that will be tested within the experimental group and within the control group. The sample of each of these groups must be large to avoid the margin of error. The larger the sample, the lower the margin of error and the greater the level of confidence in the results of the project.

The ability to replicate is the ability of the experiment to be repeated in other studies. This is very beneficial, because it allows the results you get to be tested by someone else who can prove them, increase the credibility of your study, or deny them.

The impartial Designi refers to the allocation of your experiment in a way that allows all elements of the experimental group and the control group to have the same resources, without any of them being favored. An example of this may be the location of the transgenic tomato plants in a place with a lot of sunlight. No plant is placed in the shade and its growth is disadvantaged.