Hi ky name is ni ole and i xont know the ansewer bye
Answer:
The half-life of the radioactive substance is of 3.25 days.
Step-by-step explanation:
The amount of radioactive substance is proportional to the number of counts per minute:
This means that the amount is given by the following differential equation:

In which k is the decay rate.
The solution is:

In which Q(0) is the initial amount:
8000 counts per minute on a Geiger counter at a certain time
This means that 
500 counts per minute 13 days later.
This means that
. We use this to find k.







So

Determine the half-life of the radioactive substance.
This is t for which Q(t) = 0.5Q(0). So







The half-life of the radioactive substance is of 3.25 days.
Answer:
4
Step-by-step explanation:
This is a substitution question
So we will have to substitute the value of x given into the given question
f(x)=8^x
And x is given as 2/3
So let's get to work
8^2/3 which means that cube root of 8 then square the answer
(3√8)^2
Cube root of 8 is 2
So we will have to square 2 to get 4
Therefore the final answer is 4
I believe you understand
Step-by-step explanation:
it is an imaginary no
therefore
✓-1=i