The name for such a hole is "caldera" which is a word of Spanish origin meaning "a pot" or a "cooking pot" (thing of cauldron!) - and this word is used because it resembles the shape of this hole.
Often the Calderas are filled with water forming lakes and often there is an island in the middle of the water.
<span>The ecological pyramid is the smallest at the top beacuse there is ten percent loss of energy, in the form of food, at each trophic level, and the number of organisms of the top most level are the fewest. </span>
Um, Im not sure try this website
http://www.infoplease.com/encyclopedia/us/washington-state-united-states-geography.html
Because the earth's axis is tilted. It is all about the tilt of the Earth's axis.
During the summer, the sun's rays hit the Earth at a steep angle. The light does not spread out as much, thus increasing the amount of energy hitting any given spot. Also, the long daylight hours allow the Earth plenty of time to reach warm temperatures.
During the winter, the sun's rays hit the Earth at a shallow angle. These rays are more spread out, which minimizes the amount of energy that hits any given spot. Also, the long nights and short days prevent the Earth from warming up. That's why we have winter.
I hope this helped!
Thank you,
Otaku