Answer:
I believe it is 180
Step-by-step explanation:
All triangles add up to 180
Why do you want me a little bit of
Yes but In the bigger group each person would have less
Answer:
We can use the sample about 42 days.
Step-by-step explanation:
Decay Equation:



Integrating both sides


When t=0, N=
= initial amount




.......(1)
.........(2)
Logarithm:
130 days is the half-life of the given radioactive element.
For half life,
,
days.
we plug all values in equation (1)






We need to find the time when the sample remains 80% of its original.







We can use the sample about 42 days.
No Solutions because there are too many = signs.