You would do 82.75 divided by 125 cm3 and get 0.6620 g/cm3 because to find density you mist divide mass and volume and grams is always mass and cm3 or mL is always volume. hope i helped!
CO2 is the emperical formula of carbon dioxide
The law of conservation of mass states that mass is neither created nor destroyed. Since we have 2 g/mol of A and 3 g/mol of B then AB should be equal to the sum of their molar mass that is
2 g/mol + 3 g/mol = 5 g/mol AB
for the case of A2B3
A2 = 2 * 2 = 4 g/mol
B3 = 3 * 3 = 9 g/mol
therefore A2B3 = 13 g/mol
A, because the shape of it forms and arc much like a H2O molecule.
Your answer is D rods and cones. Hope this helps!! :)