I am the scientist who is going to answer your questions. The most recant earthquakes are occurring are on the west coast of North America and the east coast of Asia.
More earthquake are likely to happen in the same spots.
There is a way to find out were the earthquakes are going to happen it is were the plates of the earth come together.
Yes there is a relationship between volcanoes and earthquakes. It is because they both happen together.
Moving together away or sliding together of the plates is what is causing earthquakes.