Answer
use goo gle
Step-by-step explanation:
Using an exponential function, it is found that it takes 18.6 days for 80% of the material to decay.
The amount of a substance after t days is modeled by:

In which:
- k is the decay rate, as a decimal.
- A(0) is the initial amount.
The half-life is of 8 days, hence
, and this is used to find k.







Hence:

The time it takes for 80% of the material to decay it t for which
, hence:






It takes 18.6 days for 80% of the material to decay.
To learn more about exponential functions, you can take a look at brainly.com/question/24906920
1. c is 4 times as many as 5 = 20
2. 27 is c times as many as 3 = 9
3. 6 times as many as c is 72 = 12
4. 8 more than c is 15 = 7
Pls give me the brainliest if these are right. Hope this helps
Answer:
The area should be 132 ft
Step-by-step explanation: