In 1914, Archduke Franz Ferdinand of Austria and his wife Sophie are shot to death by a Bosnian Serb nationalist during an official visit to the Bosnian capital of Sarajevo. The killings sparked a chain of events that led to the outbreak of World War I by early August.
Source: www.history.com
Answer:
Positive Pion, Negative Pion and Neutral Pion
Explanation:
Pi-meson or also known as pion is one of any of the three (3) subatomic particles which characterizes of being unstable of its nature. The charged pions
π+
and
π−
decay with a mean lifetime of 26.033 nanoseconds or 2.6033×10−8 seconds, and the neutral pion
π0
decays with a mean lifetime of 84 attoseconds (8.4×10−17 seconds).
Of Australia and New Zealand
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:
1) In the nineteenth century, Scandinavian and other Western European immigrants settled in this region. 2) The Ancestral Pueblo people lived in the southwestern region of the modern United States; they constructed elaborate buildings and began the American farming tradition