An endangered whale species has a population of 6000. Biologists estimate that the stock is decreasing at 3% per year. At this rate, approximately how many years will it be before only 60% of the species remains? A 9.0 years
B 9.6 years
© 10.0 years
D 16.8 years

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  D.  16.8 years

Step-by-step explanation:

The multiplier each year is 1-3% = 0.97, so the multiplier after x years is 0.97^x. You want to know the value of x when that multiplier is 60%, or 0.60.

  0.97^x = 0.60

  x·log(0.97) = log(0.60) . . . . . . take logarithms

  x = log(0.60)/log(0.97) ≈ 16.8

At the given rate, it will be 16.8 years before 60% of the species remains.

relating to or denoting a system of numbers and arithmetic based on the number ten, tenth parts, and powers of ten.

it alot will look like this 4.4

answer: #1 ads up by 8 and i don't know #2