View the Show Me More video and then answer the questions.

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Question 1
According to the video that you watched, one of the most important human inventions is blank.
Question 2
Which part of the brain contains our “internal clock?”
Question 3
In order to assess her internal click, Clarissa goes to a sleep laboratory where she will be monitored for a 24-hour period. Every hour, she gives a saliva sample, which is then tested for its blank levels.