For a given sandy soil, it is known that emax $=0\mathrm{.}75$ and emin $=0\mathrm{.}4.$ A field sample of the soil is collected using a Shelby tube. The void volume of $0\mathrm{.}37$ ft$3$ is measured. Assuming the whole volume of the soil sample is $1\mathrm{.}16$ ft$3,$ determine the relative density of the natural soil.