Answer:
it's rational for the second part it is the 1st option and the 4th option
Step-by-step explanation:
You can solve any further
Answer:
x=28
Step-by-step explanation:
Answer:
a) The half life of the substance is 22.76 years.
b) 5.34 years for the sample to decay to 85% of its original amount
Step-by-step explanation:
The amount of the radioactive substance after t years is modeled by the following equation:

In which P(0) is the initial amount and r is the decay rate.
A sample of a radioactive substance decayed to 97% of its original amount after a year.
This means that:

Then



So

(a) What is the half-life of the substance?
This is t for which P(t) = 0.5P(0). So







The half life of the substance is 22.76 years.
(b) How long would it take the sample to decay to 85% of its original amount?
This is t for which P(t) = 0.85P(0). So







5.34 years for the sample to decay to 85% of its original amount
Answer:
21a^11b^3
Step-by-step explanation:
let me know if this is right