Answer:
1 = A
2 = B
3 = B
Explanation:
1) Black holes occur when really big stars collapse on themselves. And, in order to get big, the star has to be an old one.
2) A black hole is something huge that swallows up everything, while a protostar is just the very beginning of a star.
3) Scientist can't truly know for sure, but they can infer about them due to the effects of the surrounding areas.
I would say D and A are your answers :)
Lead I believe would be the heaviest because gold is relatively light
Answer:
B.
Explanation:
Jobs are lost due to a lack of metal for computers.
