instruction:
In this task, you're given a context, further information available on a particular linked term from the statement, and an answer term. Your job is to generate a question that can use the information provided to obtain the given answer. You should use the information on both context and link information to create the question. Note that the answer to the question should be exactly the given answer, and if the answer is none, the answer to the question shouldn't be obtainable from the context or linked information.
question:
Context: In 1994, Green joined his brother Barry's Team Green as team manager, and competed in the 1994 CART IndyCar World Series with driver Jacques Villeneuve Link Information: none Answer: none
answer:
How many other drivers competed in the CART IndyCar World Series the year that Green joined his brother Barry's Team Green as team manager?


question:
Context: the last Bulgarian Tsar Ivan Shishman Link Information: 

Ivan Shishman () ruled as emperor (tsar) of Bulgaria in Tarnovo from 1371 to 3 June 1395. Answer: 24
answer:
How long did the last Bulgarian Tsar rule the Empire?


question:
Context: The road curves to the northeast and becomes Numidia Drive, heading into the Weiser State Forest and turning to the northwest as it crosses Big Mountain. Link Information: Weiser State Forest encompassed 17961 acre Answer: 17961 
answer:

How many acres is the state forest that PA 42 crosses?