An experimenter had groups of one to four people look up at the sky on a street corner and measured what proportion of people who walked by also looked up. this is an example of

an experiment.

Explanation:

An experiment refers to a scientific process that could be made to discover the things, hypothesis test and exhibit a fact i.e. known

Here in the given situation, it is mentioned that the experimenter contains a group in which one to four people are looking up to the sky on the corner of the street and also the proportion is measured

So this is an example of an experiment

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