Plz help i have no idea how to do this math

answer: this doesnt make any sense especially the photo.

step-by-step explanation:

option: d is correct

step-by-step explanation:

if you need just tell me and i will come to the rescue.

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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