Part A

A two$-$component model used to determine percent body fat in a human body assumes that a fraction $)<mi>(</mi><mn>1</mn>$ of the body's total mass $m$ is composed of fat with a density of $0\mathrm{.}90\frac{g}{c}{m}^3,$ and that the remaining mass of the body is composed of fat$-$free tissue with a density of $1\mathrm{.}10\frac{g}{c}{m}^3.$