Find amount. (1) principal- 2400, time- 7yrs, interest rate- 6.5%

look a the sides they are perpendicular

1. perpendicular

2. parallel

3. perpendicular

my guess would be b and d, but i didn’t actually get out the pen and paper. lol

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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