Please calculate the concentration (in moles/m^3) of oxygen in the air (21% oxygen) assuming it acts as an ideal gas at 20 degrees C. Oxygen diffuses to the inside of insects through tiny tubes called tracheae which average 2mm long and 2 x 10 ^-9 m^2 in cross-section. Estimate the average diffusion rate assuming the concentration of oxygen inside approaches 0. Estimate the average time it takes for a molecule to diffuse in. What is the average speed for such a molecule. What is the rms speed for such a molecule?