<span>Small jagged pieces of rocks, minerals, and volcanic glass the size of sand and silt (less than 2 millimeters (1/12 inch) in diameter) erupted by a volcano are called volcanic ash. Very small ash particles can be less than 0.001 millimeters (1/25,000th of an inch) across.</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.
The correct answer is D. Decreased travel times.
The industrial revolution revolutionized the transport as well, so in this period we have the emergence of transporting machines, like the trains for example, and they were also getting better and better as the year passed by, and they were of great help to the people, especially when they had to travel on long distances.
Christianity & Shintoism is not major factor in southeast Asia....