http://en.wikipedia.org/wiki/List_of_earthquakes#Largest_earthquakes_by_magnitude
It is impossible to tell. 2010 was a year of numerous large earthquakes around the globe. However, many smaller earthquakes occurred and many more that were too weak to be measured. It is estimated that millions of earthquakes occur each year.
One last year in Hauiku
The 8.8 magnitude earthquake in Chile and two 7.8 earthquakes in Indonesia were the most significant in 2010. List of earthquakes by year or by country can be found at the USGS Earthquake Hazards website. It provides a list of significant earthquakes for 2010 as well as a worldwide map of earthquakes for 2010. See link below.
18 on average
uhhh the Declaration of Independence on July 4th
Britney Spears went super nuts
New Zealand has many minor earthquakes a year, but only one major earthquake has happened in New Zealand in 2011.
18
Trinidad lies on a fault line. There are earthquakes fairly regularly - at least 2 per year. None have done major damage however.
Nobody knows how many earthquakes can happen in a year because you cannot predict earthquakes. :)
Yes, San Gabriel, California has experienced earthquakes. It is located near the San Andreas Fault, which is a major tectonic boundary that is known for its seismic activity. The area has a history of earthquakes, including the notable 1987 Whittier Narrows earthquake.
Yes. All known earthquakes of magnitude 9.0 or greater have occurred at subduction boundaries.