1. identify all correct answers (there may be more than one). in the expression a^b, a. the value b is an exponent. b. the value a tells you how many times to multiply b by itself. c. the value a must be > 1. d. the value b tells you how many times to multiply a by itself. e. the value b must be an integer.

it is 10.6 according to my calculations

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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