A controlled investigation is a experiment that is set for example the same rule for everything
Hope this helps
<span> Find the molar mass of calcium acetate...158.165g.
So start with 255g Calcium acetate x 1 mole Calcium Acetate/158.165 g Calcium Acetate x 6 mol Hydrogen/1 mole Calcium Acetate x 6.022e23 atoms/mole.
So...(255 x 1 x 6 x 6.022e23)/(158.165 x 1 x 1) = 5.825e24 hydrogen atoms</span>
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Density is the ratio of mass to the volume.
The mathematical expression is given as:

Now, density of isooctane = 
Volume = 
Since, 1 gallon = 3.78 L
So, 3.8 gal = 
= 
As, 1 L = 1000 mL
Therefore,
= 
Volume in mL = 
Put the values,


= 
Hence, mass of 3.8 gal of the gasoline is
.
Answer:
Steam always has more thermal energy than ice.
Explanation: