<span>amount of heat and energy(energy of fusion)</span>
I think the answer is C , more dense
Answer: 2mg
Part per million is unit that equal to mg/kg of water or simply

. In this case, you asked how much NaCl needed and know the volume of water(100mL), concentration(20ppm or 20 mg/kg) and water density.
Then, the equation would be
concentration = NaCl weight/ water weight
20 x

mg= NaCl weight/ (100ml x 1g/ml)
NaCl weight= 20x

mg/kg x 100g
NaCl weight= 2000 x

g
NaCl weight= 2x

g = 2mg
The correct way to balance would be
2H2 + O2 = 2H2O
Answer:
a - carbon is not toxic to living things
Explanation:
The reason carbon dating works is that the fresh carbon-14 gets mixed in with the rest of the carbon in the atmosphere and, since it's chemically identical to regular carbon, gets worked into whatever is presently absorbing atmospheric carbon