Answer:
it would be redshift and cosmic background radiation
The following is the arrangement of the given molecules in decreasing order of mass: 
<u>Solution:</u>
First inorder to arrange the elements in descending order of their mass we have to calculate the molecular mass of each element. The calculation is as follows:
<u>Mass of C6H14:</u>


<em>Mass of C6H14 is 86.172</em>
<u>Mass of NO2:</u>


<em>Mass of NO2 is 46.0055</em>
<u>Mass of Fe2O3:</u>


<em>Mass of Fe2O3 is 159.6882</em>
<u>Mass of CaCO:</u>


<em>Mass of CaCO will be 68.0874</em>
So, the order will be
which is 
Ethylene- C2H4 = 85.7% Carbon and 14.3% Hydrogen
Find the atomic masses for each element and multiply it by the number of atoms in the compound, then add.
C- 12.0 * 2= 24.0
H- 1.00 * 4= 4.00
-----------------------
28.0
Take the masses for each element and divide it by the total mass. Then change the answer to get the percent.
C 24.0 / 28.0= .857 = 85.7%
H 4.00 / 28.0= .143 = 14.3%
<h3>
Ethylene is 85.7% Carbon and 14.3% Hydrogen </h3>
Answer:
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Explanation:
Roughly 96 percent of the mass of the human body is made up of just four elements: oxygen, carbon, hydrogen and nitrogen, with a lot of that in the form of water. The remaining 4 percent is a sparse sampling of the periodic table of elements
Hope this helps :)