11. a grid shows the positions of a subway stop and your house the subway stop is located at (4,-2), and your house is located at (-9,-6). what is the distance, to the nearest unit, between your house and the subway stop?

a) 6
b) 9
c) 14
d) 15

you probably already have the answer but anyways it's b. 15.0

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

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