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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.
When water vapor and carbon dioxide absorb heat and either radiate it into space, to other gases, or send it back to Earth, this is the <u>Greenhouse Effect. </u>
<h3>What is the Greenhouse effect?</h3>
This is the trapping of the sun's heat by gases such as water vapor and carbon dioxide.
When the heat is trapped, it can be radiated to other gases or radiated back to the Earth. This process is responsible for the rise in temperature noted around the Earth.
Find out more on the Greenhouse Effect at brainly.com/question/19521661.
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When the hurricane touch the ground
