From the statement you can find the function that represents the percent of strontium-90 that remains after t years of the nuclear accident.
Call P the percent:
---> P = e ^ (- 0.025t)
Now you can also estimate the half-life of the isotope strontium-90:
Call Pi the initial percent and P2 the half percent:
P2 = 0.5 * P initial =>
P2 = 0.5 * Pinitial = Pinitial * e ^ (-0.025 t)
=> 0.5 = e ^ (-0.025t)
=> ln 0.5 = -0.025t
=> t = - ln (0.5) / 0.025
=> t = 27.7 years <----- half-time
1/4×1/2 is 1/8×1/5=1/40 and 200/40 =5
Answer is 5
(6 + 5i)(4 + 7i) = 24 + 42i + 20i + 35i²
= 35i² + 62i + 24
The product of 6+5i and 4+7i is 35i² + 62i + 24.
I think is A! Im not sure tell me if it’s right
Answer:
i think it is the 3 one from the left side
Step-by-step explanation:
