What is variable ?
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The egyptians invented the ? to water their crops, and may have used the ? to build the pyramids.

1. which of the following is a search engine? a) mozilla firefox b)internet explorer c)google d)safari 2. which of the following statements is true? a) all search engines will provide the same results when you enter the same query. b) all search engines use the same amount of advertisements. c) some search engines are also browsers. d) search engines often provide different results, even when you enter the same query.

Which feature is selected to practice and save the timing of a presentation