A rocket launched upward from a 160 foot cliff with an initial velocity of 48 ft/secPart A- write a function to model the height of the rocket. Part B- Find the time it takes the rocket to reach the ground at the bottom of the cliff

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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how many friends does he have? i think some of the information got cut off in the problem.