Answer:
D) the steady, clocklike decay of certain radioactive isotopes over time.
Explanation:
Geologists use radiometric dating to estimate how long ago rocks formed, and to infer the ages of fossils contained within those rocks.
For example, when rocks are formed, such as igneous rocks (formed when molten rocks cools), certain radioactive atoms are trapped inside the rocks during this formation process. Then these radioactive atoms decay over time.
The age of the rock can be estimated by comparing the occurring radioactive isotope within the material to the abundance of its decay products, which form at a known constant rate of decay.
From the options;
A) this is about the formation of the radioactive molecules and not about radiometric dating
B) this is radiocarbon dating (cabon dating/carbon-14 dating)
C) the <em>assumption </em>is wrong since the radioactive isotopes decays not accumulate.
D) the corect option as I explained earlier.
Answer:
The imaginary vertical lines that run from the North pole to the South pole on a map are called longitudinal lines. The equator is equidistant from the North and South poles. Then, the equator separates the northern and southern hemispheres.
Explanation:
After Fidel Castro came to power in Cuba, he did two things that upset the United States immediately, he implemented the communist doctrine in the country, and he allied with the Soviet Union.
The implementation of communism in Cuba meant that everything that was private went into the possession of the government, including lot of companies that were owned by US citizens. That move was seen as robbery by the United States, as their citizens literary got their possessions confiscated without being paid anything.
The alliance with the Soviet Union upset and scared the United States. That move meant that their arch enemy will have influence over the island, and also probably make a military base just right of the coast of the United States, so that put them in a very bad tactical and strategic position.
Fractional Crystallization