I'm using 22 inches as the average circumference of a female's head and estimating it to be roughly spherical. I converted inches to centimeters and calculated the volume to be 2,946.58 cm³ or 2.95 L. How would I find the mass of air it takes to fill up that volume?

mass =density * Volume
density of air = 1.1839 kg/m^3 at 25C....... m^3 =1000 L
= 1.1839 /1000 = 1.1839 * 10^3 kg/L
volume of sperical = 0.524 d^3
from circumference=3.14* d..............
22inch = 55.88cm..............1 Inch = 2.54 cm
d = 55.88 *3.14 =17.796cm
volume = 0.524 * 17.8^3 = 2953cm^3 ..........cm^3 =1ml ................ml =0.001 L
volume in L = 2.95 L
mass = density * Volume =1.1839 * 10^3 kg/L * 2.95 L = 3.493 * 10^3 Kg = 3.493 g
density of air = 1.1839 kg/m^3 at 25C....... m^3 =1000 L
= 1.1839 /1000 = 1.1839 * 10^3 kg/L
volume of sperical = 0.524 d^3
from circumference=3.14* d..............
22inch = 55.88cm..............1 Inch = 2.54 cm
d = 55.88 *3.14 =17.796cm
volume = 0.524 * 17.8^3 = 2953cm^3 ..........cm^3 =1ml ................ml =0.001 L
volume in L = 2.95 L
mass = density * Volume =1.1839 * 10^3 kg/L * 2.95 L = 3.493 * 10^3 Kg = 3.493 g