What kinds of scientific investagations involve making observations

Scientific investigations that involve some kind of testing will make use of observations.  Generally speaking, making observations is the first step of the scientific method.  Based on those observations, a question is asked, and then a hypothesis and prediction will be stated.  A scientist will set up a test, observe the outcome, and collect data on the test.  That will lead the scientist to some kind of conclusion relating to the initial question and hypothesis

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