Both petroleum and coal are made up of complex carbon-based molecules, and both originated with living creatures of some kind. both are vital sources of energy for the modern world and both were formed by geologic processes over millions of years. however, petroleum was mainly formed from the remains of ocean-dwelling microorganisms. coal, on the other hand, originated from decayed vegetation in ancient swamps and bogs. in any case, it took millions of years for both coal and oil to be produced. this is the case because it took that much time for overlying sediments to produce the unimaginable heat and pressure that would one day allow us to harvest these energy resources. what is one clue word or phrase in the passage that indicates a contrast? a. however b. in any case c. both d. because

What is the meaning of the word checking as it is used in this sentence from the second paragraph of the passage?

Which two pieces of evidence support the idea that coal is underutilized? this was on study island about coal

M read the sentence.what best describes the underlined part of the sentence,and why? alma plans to visit london and paris, where her parentswent on their first trip together as a married couple.it is a restrictive relative clause because it begins with arelative pronoun, has both a subject and a verb, and is notnecessary to the meaning of the sentence.it is a nonrestrictive relative clause because it begins witha relative pronoun, has both a subject and a verb, and isnecessary to the meaning of the sentence.it is a restrictive relative clause because it begins with arelative pronoun, has both a subject and a verb, and isnecessary to the meaning of the sentence.it is a nonrestrictive relative clause because it begins witha relative pronoun, has both a subject and a verb, and isnot necessary to the meaning of the sentence.