Which factor in Adam Sobieski's research made him feel
uncertain about visiting Death Valley? Use two details from the
article to support your response.

Miners who has visited the valley found it inhospitable and dangerousThat the valley is a place where lots of records are shatterd in a spot.

Explanation:

In stating the obvious reasons from the article research on why Adam Sobieski's felt uncertain about visiting the Death Valley, we support his reasons with the following two points:

Based on what Adam Sobieski's research, some miners who have visited the place found it inhospitable and a very dangerous place.He also found out that the Valley is a place where lots of records have been broken in just a single spot.We must also add that the name of the place "Death Valley" alone has scared off travelers from going for a visit to the Valley.

It may be written down (as in the united states) or it may be unwritten (as in great britain). this is the 1787 meeting at which the  constitution of the united states  was debated and agreed upon. this was a 1787 meeting called by congress to amend the articles of the confederation.