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:
The manufacture and use of these releases another greenhouse gas to the atmosphere, nitrous oxide. Therefore, increased use of fossil fuels and changes in agriculture have both contributed to the increase in global temperatures because they have both caused the release of more greenhouse gases into the atmosphere.
Explanation:
Mark this as brainiest please ;)
<u>Answer</u>:
This is due to the unequal resource distribution across the land and the distribution of resources depends upon the physical factors like the land and the climatic conditions. Some places are filled with more resources while some are filled with scare resources. The countries which have more resources are wealthy while the countries which do not have that much resources are not wealthy. The metals are also unevenly distributed on the earth’s crust and the most abundant metal is aluminum and silicon. Some of the distracted metals which are found deep in the earth’s crust and then extracted in the ore form from the mines. The most important reason for the uneven distribution of metals in Earth's crust are their physical factors like the climate, land and their topography.
Atmosphere, the global sum of all ecosystems, and the kithosphere
Folk culture is more likely to have an anonymous origin and to diffuse slowly through migration, whereas popular culture is more likely to be invented and diffuse rapidly with the use of modern communication.
