Yreliability a survey with 12 questions is designed so that 3 of the questions
identical and 4 other questions are identical
er questions are identical (except for minor changes in wording). how many
different ways can the 12 questions be arranged?
h he stores all of his great ideas

lo ; )

the answer is c. ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀

ending amount = beginning amount / (2^n)

where "n" = number of half-lives (or elapsed time / half-life)

ending amount = 50 mg / (2 ^10 / 5.3)

ending amount = 50 mg / (2 ^ 1.8867924528)

ending amount = 50 m / 3.6981210597

ending amount = 13.5203794557 mg

or about 13.5 mg remain

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