This right rectangular prism is filled with -foot unit cubes. What are the actual dimensions of the prism?
How many unit cubes are in this prism?
What is the total volume of the prism, in cubic feet?

the answer is b

idk

step-by-step explanation:

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

source:  

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