C. $1,185.50 D. $1,195.50
The position of a particle is given as x(t) = cos(3t) - sin(4t). Find the acceleration of the
particle at t = 0.
A. - 9
B. 0
C. 1
D. 16

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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