Answer:
![t=4820 y](https://tex.z-dn.net/?f=t%3D4820%20y)
Step-by-step explanation:
a) The half-life equation is given by:
![t_{1/2}=\frac{ln(2)}{k}](https://tex.z-dn.net/?f=t_%7B1%2F2%7D%3D%5Cfrac%7Bln%282%29%7D%7Bk%7D)
b) Using the decay equation we have:
![Q(t)=15e^{-0.0001438t}](https://tex.z-dn.net/?f=Q%28t%29%3D15e%5E%7B-0.0001438t%7D)
we need to find t when ![Q(t)=\frac{Q_{0}}{2}](https://tex.z-dn.net/?f=Q%28t%29%3D%5Cfrac%7BQ_%7B0%7D%7D%7B2%7D)
![7.5=15e^{-0.0001438t}](https://tex.z-dn.net/?f=7.5%3D15e%5E%7B-0.0001438t%7D)
![0.5=e^{-0.0001438t}](https://tex.z-dn.net/?f=0.5%3De%5E%7B-0.0001438t%7D)
![ln(0.5)=-0.0001438t](https://tex.z-dn.net/?f=ln%280.5%29%3D-0.0001438t)
![t=\frac{ln(0.5)}{-0.0001438}](https://tex.z-dn.net/?f=t%3D%5Cfrac%7Bln%280.5%29%7D%7B-0.0001438%7D)
![t=4820 y](https://tex.z-dn.net/?f=t%3D4820%20y)
Therefore, it will take 4820 years to decay to half the original amount.
I hope it helps you!
L = B + 105
H = L + 24.....H = B + 105 + 24 ...H = B + 129
H + L + B = 324
(B + 129) + (B + 105) + B = 324
3B + 234 = 324
3B = 324 - 234
3B = 90
B = 90/3
B = 30 <==Bart's marbles
L = B + 105
L = 30 + 105
L = 135 <=== Lisa's marbles
H = B + 129
H = 30 + 129
H = 159 <=== Homer's marbles
Answer:
$1.98
Step-by-step explanation:
6%=0.06
33*0.06=1.98
Answer:
-10c
Step-by-step explanation:
16x
-26c/x
-----------
-10c
Answer:
It will take it 1 and 1/2 hours.
Step-by-step explanation:
Because they walk 5/6 miles in 5/4 hours we can set up a proportion. They walk 1/6 miles in 1/4 hour. Now using the proportion we can find out that they walk 1 full mile or 6/6 of a mile in 6/4 hours or 1 and 1/2 of an hour.