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Iq scores for adults age 20 to 34 years are normally distributed according to n(120, 20). in what range does the middle 68% of people in this group score on the test?

Awater holding tank measures 105 m long, 50 m wide, and 8 m deep. traces of mercury have been found in the tank, with a concen- tration of 60 mg/l. what is the total mass of mercury in the tank? answer in units of kg.

Which of the following can be used to explain a statement in a geometric proof?