Hello!
The primary advantage of multiple researchers obtaining the same result is the conclusion is likely to be more credible when they are independently verified. As the work done by them gives the same result, it can be easier to believe.
Answer:
3.9 billion years
Explanation:
The half-life of potassium-40 is the time it takes for half of it to decay.
After one half-life, half of the original amount will remain.
After a second half-life, half of that amount will remain, and so on.
We can construct a table as follows:

We see that the mass will drop to 10 g after three half-lives.
1 half-life = 1.3 billion years
3 half-lives = 3.9 billion years
Answer: cartilage
Explanation: because it is not hard or soft but it still is bone and that is what your ears and nose is made of