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

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]
seal illegally is broken

Why did Grand Duchy of Lithuania become a famous place for noble Ruthenian families to get intermarried?, Context: In Ruthenia the nobility gradually gravitated its loyalty towards the multicultural and multilingual Grand Duchy of Lithuania after the principalities of Halych and Volhynia became a part of it. Many noble Ruthenian families intermarried with Lithuanian ones.
after the principalities of Halych and Volhynia became a part of it

What are gets less dust from the Sahara than the Caribbean?, Context: NASA's CALIPSO satellite has measured the amount of dust transported by wind from the Sahara to the Amazon: an average 182 million tons of dust are windblown out of the Sahara each year, at 15 degrees west longitude, across 1,600 miles (2,600 km) over the Atlantic Ocean (some dust falls into the Atlantic), then at 35 degrees West longitude at the eastern coast of South America, 27.7 million tons (15%) of dust fall over the Amazon basin, 132 million tons of dust remain in the air, 43 million tons of dust are windblown and falls on the Caribbean Sea, past 75 degrees west longitude.

Amazon basin