Answer:
1. 1343 years
2. 9 hours
3. 39 years
Step-by-step explanation:
1. Given, half-life of carbon = 5730 years.
∴ λ = 0.693/half-life of carbon = 0.693/5730 = 0.000121
If N₀ = 100 then N = 85
Formula:- N = N₀*e^(-λt)
∴ 85 = 100 * e^(-0.000121t)
∴㏑(-0.85)=-0.000121t
∴ t = 1343 years
2. Given half-life of aspirin = 12 hours
λ = 0.693/12 = 0.5775
Also N₀ = 100 then 70 will disintegrate and N = 30 will remain disintegrated.
∴ 70 = 100 *e^(-0.05775t)
0.70 = e^(-0.05775t)
㏑(0.70) = -0.05775t
∴ t = 9 hours
3. The population of the birds as as A=A₀*e^(kt)
Given that the population of birds fell from 1400 from 1000, We are asked how much time it will take for the population to drop below 100, let that be x years.
The population is 1400 when f = 0, And it is 1000 when f = 5
We can write the following equation :
1400 = 1000e^(5t).
∴1400/1000 = e^(5k)
∴ k = ㏑(1.4)/5
We need to find x such that 1400/100 = e^(xk)
14 = e^(xk)
∴ x = 39 years
Hello there k12 user. - i am in k12 too :)
cough.
use mathpapa look it up it should give your anwser i cant copy and paste it, but its there
just put in the numbers
Answer: 6 m
Step-by-step explanation:
The area of a rectangle is the length times the width.
We can set up an equation.
108 m^2 = 18 m * width
Width = 6 m
Answer:
x = tex]5\frac{\textup{7}}{\textup{8}}\ in[/tex]
Step-by-step explanation:
Given:
Total height of the bench = 18 in
Depth of the stone bench =
= = 3.375 in
Measure of stones =
= = 3.5 in
measure of another stone =
= = 5.25 in
let the height of the third stone be 'x'
Now,
The total height of the bench = depth of bench + Measure of two stones + x
18 = 3.375 + 3.5 + 5.25 + x
or
x = 18 - 12.125
or
x = 5.875 in
or
x = tex]5\frac{\textup{7}}{\textup{8}}\ in[/tex]
X^2 + 3x - 6
This is because x^2 and 3x have nothing they can combine with, leaving them as their own number. 1 + - 6 will give you -5 as adding to a negative only reduces not adds entirely.
Hope this helps!