The isotope known as carbon-14 is radioactive and will decay into the stable form nitrogen-14. As long as an organism is alive, it ingests air, and the level of carbon-14 in the organism remains the same. When it dies, it no longer absorbs carbon-14 from the air, and the carbon-14 in the organism decays. The half-life of carbon-14 is 5770 years. Assume an organic sample is 18,000 years old.

How many half-lives is 18,000 years? (Round your answer to two decimal places.)
half-lives

answer: plz mark me brainliest

7 hours, 0 minutes, 0 seconds

or:  

0.04

total weeks

or:  

0.29

total days

or:  

7.00

total hours

or:  

420.00

total minutes

or:  

25,200.00

total seconds

step-by-step explanation:

ιт ιѕ в. 1/4

ιи (fяα¢тισи/єχα¢т fσям) 1/4

ιи (∂є¢ιмαℓ fσям) .25

нσρє ι ¢συℓ∂ нєℓρ уα

x^2 + 81

we can factor this using difference of square binomials.

rewrite the equation:

x^2 - (-81)

factor:

(a^2 - b^2) = (√a^2 + √b^2)(√a^2 - √b^2)

(x^2 - (-81) = (x + √-81)(x - √-81)

we can remove the - from under the radical by multiplying it by i.

(x^2 - (-81) = (x + i√81)(x - i√81)

(x^2 - (-81) = (x + 9i)(x - 9i)

we can check our answer by using foil:

x^2 - 9ix + 9ix - 81i^2

x^2 - 81^2

i^2 = -1

x^2 + 81