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when we design experiments, we usually choose just one thing to change.for example, let’s say a farmer wants to know what kind of plowing method is better.the farmer chooses two fields and then changes only one thing between them.he changes how he plows his fields.everything else will be the same on both fields: the type of crop he grows, the amount of water that he uses and the slope of the fields he plants on.the fields should be facing the same direction to get about the same amount of sunlight.if the farmer only changes how he plows his fields, he can see the impact of the one change.after the experiment is complete, the farmer can conclude which plowing method is better/

- to avoid any ( a ) in an experiment, we had better make only one( b ) when we design an
experiment.

(a) (b)
1, confusion method
2. error project
3. fault solution
4. mistakechoice
5. interfernce vaiable이 문장을 요약하고자 한다. (a)와(b)에 들어갈 말로 가장 적절한 것은??

시험 문제인데... 답이 5번이래요... 4번 아닌가요???