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.
If a rational function is not continuous, it'll be due to one of two reasons. Either it has a hole, or it has an asymptote. Plug in -5 for x in the denominator of the rational function. What do you get? You get zero in the denominator, meaning the function is undefined at x=-5.
Answer: Biased: Opinionated
Unbiased: Actual facts / not opinionated
Step-by-step explanation:
Answer:
a. is 0.75 and b. is 0.4375
Step-by-step explanation:
just picture it as a division problem
3 divided by 4 = 0.75
and the other one 0.4375