Why is it important that an experiment include a control group? 0 а
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A control group is required for the development of an "if... then" statement.
The control group provides a reserve of experimental subjects.
A control group provides a reference by which to determine if a particular outcome may reasonably result from the variable being
tested.
A control group assures that an experiment will be repeatable.
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*will mark brainliest* certain species of are now recognized as indicators of environmental pollution. a. lichen b. mushroom c. yeast d. none of the above

Which of the following birds remained ancient looking in the miocene epoch? a. crows b. owls c. grouses d. none of the above

25) a student takes four samples of a white crystalline solid and places each in a well plate. on top of each sample, she carefully places 20 drops of clear mystery liquids a, b, c and d. her results for each well are: liquid a: the solid dissolves quickly. liquid b: the solid appears unchanged. liquid c: a brownish colored liquid is produced. liquid d: fizzing occurs and the well becomes warmer. in which well does a physical change occur?