The correct answer is D: Group 4.
A control group in an experiment is a group separated from the other groups, where the variable that is being tested cannot influence the results. In this case, different materials are the independent variable that you test. Effects of that independent variable on the melting rate of ice are excluded in the control group.
Answer:
The Fossil Record
Fossils provide evidence that organisms from the past are not the same as those found today, and demonstrate a progression of evolution. Scientists date and categorize fossils to determine when the organisms lived relative to each other.
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Answer:
<h3>
Blue whales </h3>
Explanation:
Blue whales are the largest animals ever known to have lived on Earth. These magnificent marine mammals rule the oceans at up to 100 feet long and upwards of 200 tons. Their tongues alone can weigh as much as an elephant. Their hearts, as much as an automobile.
Answer:
Student 1’s methods would be more accurate, because the student would control more factors. Only one variable at a time (either temperature or acidity) would be tested on each group of worms. On the other hand, Student 2 is testing both factors on all the worms, which could make the results unclear.