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 
to see if its copatible with our environment or to see if there is any unkown element, otherwise i dont know
if wrong very sorry
The mass of titanium is = 47,867 g/1mol
Applying the rule of avrogado
1mol _______ 6,023 × 10^(23) at
0,075mol ___ x
X . 1mol = 0,075mol . 6,023 . 10^(23)at
X = 0,075 . 6,023 . 10^(23) at
X = 4,51 . 10^(22) atoms
Hope this helps