<PRE><B>Question 731407</B>
You would want to use the density in grams per cubic centimeter. 
1 m = 100 cm
1 kg = 1000 g


{{{800 * (1000) * (1/100)*(1/100)*(1/100)}}}  (kg/m^3)(g/kg)(m/cm)(m/cm)(m/cm)
={{{0.800}}} g/cm^2


Bottle is filled to 50 cm^2, so this is {{{50*0.800=40}}} grams.


Combined weight of bottle and filled contents is {{{40+24.5=64.5}}} grams.</PRE>