Answer:
Radiometric dating of basalt on the ocean floor provide us with an absolute age for the planet earth because the oceanic crust is recycled too frequently at subduction zones,
Explanation:
Radiometric dating of basalt on the ocean floor can not provide us the absolute age of the planet earth due to the subduction. In the process of subduction oceanic plate went below the continental plate as it is less denser. It then melts there and its recycling takes place frequently. So the radiometric dating of basalt on oceanic plate can not provide us the true information regarding the age of the earth.
The United States is an example of Democracy.
Answer: In Medieval Europe, knights pledged loyalty to vassals, who in turn pledged theirs to powerful lords, and serfs labored in the fields.
Explanation:
A rigid hierarchy refers to one where people who are born into a certain position in life, find it quite hard to move from it or rather one where there are different social classes and people had to be classified in one class for the system to work.
The system during medieval times was much like this. Social classes existed that determined a person's worth in society such as the knights, vassals, Lords and Royals. There was also the serfs who were considered the lowest in the hierarchy.
Answer:
Basaltic magma -- SiO2 45-55 wt%, high in Fe, Mg, Ca, low in K, Na
Andesitic magma -- SiO2 55-65 wt%, intermediate. in Fe, Mg, Ca, Na, K
Rhyolitic magma -- SiO2 65-75%, low in Fe, Mg, Ca, high in K, Na
Explanation:
