In ΔIJK, k = 7.2 cm, ∠J=55° and ∠K=67°. Find the length of i, to the nearest 10th of a centimeter.

6.6

Step-by-step explanation:

the answer to your question is b.

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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