the graph shows calculations for potassium - argon dating. which statement explains what geologists can…

the graph shows calculations for potassium - argon dating. which statement explains what geologists can learn from the graph? they can estimate that all the potassium will have decayed within 6.5 billion years. they can tell that 1/8 of the argon gas will be left after 3.9 billion years. they can determine that a rock is 1.3 billion years old if 1/2 of the potassium has decayed. they can see that potassiums half - life varies from every 1.3 billion years to every 5.2 billion years.

the graph shows calculations for potassium - argon dating. which statement explains what geologists can learn from the graph? they can estimate that all the potassium will have decayed within 6.5 billion years. they can tell that 1/8 of the argon gas will be left after 3.9 billion years. they can determine that a rock is 1.3 billion years old if 1/2 of the potassium has decayed. they can see that potassiums half - life varies from every 1.3 billion years to every 5.2 billion years.

Answer

Brief Explanations:

  • For the first option: Radioactive decay is an exponential process, and it never truly reaches zero. So, saying all potassium will decay within 6.5 billion years is incorrect.
  • For the second option: The graph shows the remaining portion of potassium, not argon. So, this statement is wrong.
  • For the third option: When half - life occurs, if the initial amount of potassium is considered as (1), when half ((\frac{1}{2})) of it has decayed (remaining (\frac{1}{2}) of potassium), from the graph, the time is (1.3) billion years.
  • For the fourth option: Half - life is a constant for a particular radioactive substance. Potassium's half - life is a fixed value (in this context, related to the time when the remaining potassium is halved), and it does not vary as stated.

Answer:

They can determine that a rock is 1.3 billion years old if 1/2 of the potassium has decayed.