The energy transformation occurs in a gasoline-powered car is c<span>hemical energy is converted into mechanical energy. The answer is letter A. The rest of the choices do not answer the question above.</span>
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
.
Protons: charge +1, have a mass of 1 and are found in the nucleus
Neutrons: charge 0, have a mass of 1 and are found in the nucleus
Electrons: charge -1, have a mass of 1/840 and are found on the outside of the nucleus
hope that helps
500 mg in g :
1 g ----------- 1000 mg
? -------------- 500 mg
500 x 1 / 1000 => 0.5 g
total mass:
50 g + 0.5 g + 0.1 g => 50.6 g
hope this helps!