If a neutral compound is composed of carbon and hydrogen and you know that it has exactly 2 carbons connected by a double bond, how many hydrogens will the compound have?
A. 4
B. 8
C. 2
D. 6

The answer is A. 4

Explanation: I just had this question on a quiz

the mantle

explanation:

earth is divided into three layers: the crust or the outermost layer on which we live; the underlying, middle layer - the mantle - and the core (the innermost layer of earth).

the answer is b because, investigating whether another species of moth also drinks tears might be interesting, but it would not directly explain why this species of moth does.

to explain why this species of moth drinks tears, the scientist could ask: "what nutrients that moths need are in elephant tears? "

the scientist could experiment with moth repellent or oter ways to keep the moths away, but that would not answer his original question.