Answer:
a) how scientists locate black holes
Explanation:
Punctuation is used to structure and organize the writings. It helps in making more sense and clarity in the sentence.
The sentence which is written correctly is Charles Dickens was a British author who wrote Oliver Twist, David Copperfield, and Great Expectations.
This sentence is correct because it uses the punctuation mark comma appropriately to make logical groupings. Also, it helps in segregating one list from another. Hence, the above sentence comma is used to separate a series of phrases.
A. There should be an apostrophe on the it's, because it is saying, "only some of it is clean and safe enough to drink." The apostrophe should be on that word because it breaks the word down into it is, which is correct in the sentence.
Answer: I think it's this, Minerals, fresh water, and biosphere resources are distributed unevenly around the planet as a result of past geologic processes.
Explanation: Hope it helps!