Answer:
B and C
Explanation:
B. In a given rock sample, the amount of Silicon-32 isotopes gets divided in half about every 170yrs.
This is the concept of half-life. Half life is the time take for half of a radioactive isotope to disintegrate. The shorter the half life the faster the isotope disintegrates.
From the question, we were told that it would take 170yrs for half of the isotope of Silicon to disintegrate to Phosphorus. This is the half life.
C. The half life can be used to determine the amount of Si-32 that has decayed from the time closure temperature was reached.
The closure temperature is very important in radioactivity. It is the temperature at which a system has cooled and there is no resulting disintegration of parent and daughter isotopes.
From first order kinetics, we know that the rate at which radioactive elements decay at any time is directly proportional to the number of radioactive atoms present. A knowledge of the half life helps to figure out the number of atoms that has decayed in time.
Answer:
South Africa, Lesotho, and Angola are some examples of African countries that aren't located within the Sahara Desert.
Explanation:
There are a lot of African countries outside of the Sahara, are there answer choices or a specific country that is the answer? or can it be any of them?
To learn about the cultures and all that great stuff
Answer:
Limited Government: Has documents, a group of people, and some sort of checks and balances limiting the power of the government. You have the right to vote and have a lot more freedom than Unlimited Government has. ... You do not get the right to vote, and do not get the same amount of freedom that limited government has.
