To be able to step it up or down depending on need.
sharon kalunda answered the question on April 5, 2019 at 10:14
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Date posted: April 5, 2019. Answers (1)
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Date posted: April 5, 2019. Answers (1)
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Date posted: April 5, 2019. Answers (1)
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Date posted: April 5, 2019. Answers (1)
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In an experiment using a photo cell, ultra violet light of varying frequency strikes a metal
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Date posted: April 5, 2019. Answers (1)
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Date posted: April 5, 2019. Answers (1)
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Date posted: April 5, 2019. Answers (1)
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Date posted: April 5, 2019. Answers (1)
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Date posted: April 5, 2019. Answers (1)