Oliver picks a 4-digit even number that is greater than 3000. The second digit is a multiple of 4.

How many different numbers could Oliver pick?

Please help me!!! The right answer is 699, but please be really kind to show me the working out

the answer is 8

step-by-step explanation:

3.14 x 8x8

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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