Answer: The correct requirement for a black hole to form is:
C. The star must be 10 to 28 times larger than Earth’s sun, and a supernova explosion must have occurred.
Explanation: The least star that is larger than the sun is 10 times larger and a supernova explosion would have happen before a black hole to form.
If this is a true or false question, the answer is false. United States do share land borders with Mexico as well as Canada along with Russia, Bahamas and Cuba. United States then is north of Canada and south of Mexico. Hope this is the answer.
Medicine and safety regulations at the work place.