Answer:
cause of the harmful radiation of the sun
Explanation:
cause of the harmful radiation of the sun
The best bibliogaphic entry would probably be: Smythe, Clark. <em>Unsinkable: Folly on the Titanic</em> Little, Brown: New York, 1976.
That is because it seems to be a book about the Titanic itself, whereas the other ones have to do with:
- topics which are less directly related to the subject-matter (the first entry is about maritime laws and the third one is about the animal and plant populations of the lands near the North Pole),
- personal, relative accounts of the events (like the fourth entry, which is an autobiography of a survivor and therefore describes the wreck through the character's own perspective) as opposed to more factual material.
The coolest layer is the crust. The crust is on the surface of the earth (where we are) . Inner Core
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:
B. Heat and Pressure
Explanation:
This is because metaphoric rocks are formed due to change in texture and composition of the pre-existing rocks...
