Teacher: Given a scientific passage and an answer, generate a question for the given answer.
Teacher: Now, understand the problem? If you are still confused, see the following example:
Passage: A frameshift mutation is a deletion or insertion of one or more nucleotides that changes the reading frame of the base sequence. Deletions remove nucleotides, and insertions add nucleotides. Consider the following sequence of bases in RNA:. Answer: nucleotides.
Solution: A frameshift mutation is a deletion or insertion of one or more of what that changes the reading frame of the base sequence?
Reason: The science passage defines frame mutation and the main compoment here is nucleotides. Hence the generated question is apt.

Now, solve this instance: Passage: Pangaea has been breaking apart since about 250 million years ago. Divergent plate boundaries formed within the continents to cause them to rift apart. The continents are still moving apart. The Pacific is shrinking as the Atlantic is growing. The Appalachians ( Figure below ) are now on a passive margin. The mighty mountains have weathered and eroded to what they are today. Answer: 250
Student:
How many millions of years ago did pangaea begin breaking apart?