Which of the following is an unanswered question about life on earth?
a) how long has life existed on earth?
b) what were early forms of life like?
c) did early life arise spontaneously or did it come from space?
d) how does evolution occur?

Answer;

C) Did early life arise spontaneously or did it come from space?

Explanation;

-Many theories of the origin of life have been proposed, but since it's hard to prove or disprove them, no fully accepted theory exists.

-The answer to this question (Did early life arise spontaneously or did it come from space?) would not only fill one of the largest gaps in scientists' understanding of nature, but also would have important implications for the likelihood of finding life elsewhere in the universe.

emerald ash borer

the emerald ash borer is a green buprestid or jewel beetle native to north-eastern asia that feeds on ash species. females lay eggs in bark crevices on ash trees, and larvae feed underneath the bark of ash trees to emerge as adults in one to two years. hope this !

the relative atomic mass of an element is the mass of one atom of that element, relative to 1/12th of the mass of a  1212c atom. to convert to an absolute mass in kg, it is necessary to multiply by  1.661×10−271.661×10−27.

the relative atomic mass is roughly equal to the number of neutrons, plus the number of protons, in the nucleus of the atom.

for elements with more than one stable isotope (different types of nucleus with different numbers of neutrons but the same number of protons), the quoted mass is usually the average mass, weighted by the relative abundance of the different isotopes.