In what region have damaging earthquake been concentrated

Earthquakes are frightening and often dangerous to Earth. The disturbances in Earth’s crust causes destructions and fatality. The world’s seismic energy is release in the form of damaging earthquakes  have been concentrated along the Pacific Ocean where it meets the Western coast of North, Central and South America. Specifically, west of the Rocky Mountains, from California to Alaska, in Missouri and reaches across Japan, Philippines, Indonesia, China and Australia.

r just means there's a number of carbon in teh chain. for example rcooh means that after x number of carbon, the chain ends with cooh.

explanation:

answer; economic order quantity;