In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

Q: What would an engine driver have to do to adjust the more modern type of valve?, Context: Steam engines frequently possess two independent mechanisms for ensuring that the pressure in the boiler does not go too high; one may be adjusted by the user, the second is typically designed as an ultimate fail-safe. Such safety valves traditionally used a simple lever to restrain a plug valve in the top of a boiler. One end of the lever carried a weight or spring that restrained the valve against steam pressure. Early valves could be adjusted by engine drivers, leading to many accidents when a driver fastened the valve down to allow greater steam pressure and more power from the engine. The more recent type of safety valve uses an adjustable spring-loaded valve, which is locked such that operators may not tamper with its adjustment unless a seal illegally is broken. This arrangement is considerably safer.[citation needed]

A: seal illegally is broken
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Q: How was access gained to Alaska, Context: The specifics of Paleo-Indian migration to and throughout the Americas, including the exact dates and routes traveled, provide the subject of ongoing research and discussion. According to archaeological and genetic evidence, North and South America were the last continents in the world with human habitation. During the Wisconsin glaciation, 5017,000 years ago, falling sea levels allowed people to move across the land bridge of Beringia that joined Siberia to north west North America (Alaska). Alaska was a glacial refugia because it had low snowfall, allowing a small population to exist. The Laurentide Ice Sheet covered most of North America, blocking nomadic inhabitants and confining them to Alaska (East Beringia) for thousands of years.

A: the land bridge
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Q: Who made a treaty with France in a year sometime after 1793?, Context: When revolutionary France declared war on Great Britain in 1793, the United States sought to remain neutral, but the Jay Treaty, which was favorable to Great Britain, angered the French government, which viewed it as a violation of the 1778 Treaty of Alliance. French privateers began to seize U.S. vessels, which led to an undeclared "Quasi-War" between the two nations. Fought at sea from 1798 to 1800, the United States won a string of victories in the Caribbean. George Washington was called out of retirement to head a "provisional army" in case of invasion by France, but President John Adams managed to negotiate a truce, in which France agreed to terminate the prior alliance and cease its attacks.

A:
President John Adams
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