Ben's latest journey will take him from Tokyo to San Francisco, and is set to last for five months. That's 5,500 miles worth of swimming, the first-ever attempt by someone to cross the Pacific in this way. Ben will be swimming eight hours<span> a day at the average speed of two to two and a half knots per hour</span>
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.
Nitrogen and oxygen are the main constituents of the atmosphere plus water vapour near the surface. Carbon dioxide is present in smaller amounts butgl of course it can have a profound influence on the climate as global warming has shown, Greenhouse gases include water vapour, carbon dioxide, methane and nitrous oxide.
Olympia is the capital of Washington
I believe its b , hope it helps