The gas, nitrogen, is found in dry air at sea level at a concentration of 78.1 percent by volume. What is the concentration of N, expressed in ppm?

If the concentration of phosphate in the cytosol is 2.0 mm and the concentration of phosphate in the surrounding fluid is 0.1 mm, how could the cell increase the concentration of phosphate in the cytosol? a) passive transportb) diffusionc) active transportd) osmosise) facilitated diffusion