On May 18, 1980, a massive eruption of Mt. St. Helens in Washington State sent a huge plume of ash more than 50,000 feet into the air. Over the next two weeks, the ash traveled around the world. To move that far, the ash would've had to:. a. reach into the stratosphere. b. dissolve in the nitrogen of the air. c. bind to aerosols in the lithosphere. d. combine with moisture in the troposphere.

b. dissolve in the nitrogen of the air.

Explanation:

We can say that volcanic ash travels long distances when mixed with nitrogen in the air. Nitrogen is one of the most prevalent elements in the air and that is why it is so easy for ash to move. Furthermore, this is why they are so harmful to humans, as they can be breathed.

Volcanic ash can be moved through the air in large quantities, when this happens, the event is called a plume of ash, as it promotes the movement of real ash columns.