what is the mass of co2 in the atmosphere today (use concentration = 400 ppm)? what is the mass of methane (ch4 concentration = 1.9 ppm)?

The density of water is 1 g/cm cubed and in order for the pebble to sink its density has to be greater than the density of water and in order for the twig to float its density has to be less than the density of water

I'm sorry but i'm only grade

Answer(28.02g/mol);