When people perform experiments of any sort, the professional people only change one variable so that they know what is being changed. For instance if I compared the effect of the growth of flies, and one group had more food and cleaner water, and the other group had neither, it would be pointless. It would be pointless because even if the experimental results were a success, you wouldn't know for sure which variable caused the change, the water or the food variable. That's why there can only be one man-made variable at a time.
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Answer:
Correct answer is C. Renaissance period.
Explanation:
Options A and B are not correct because term Dark Ages is sometimes used to describe the Middle Ages, and that was a period when knowledge was not in the focus of attention. Illiteracy was dominating the life of people.
C is correct because during the Renaissance the revival of knowledge was in the focus of attention and that is why this translation were very important.
D is not correct as industrial revolution was started due to certain technological improvements.
I think the answer is going to be Nelson Mandala
The mass is how much space an object takes up while weight is the measure of the matter.