a∝1ma \propto \frac{1}{m}a∝m1
a∝m\mathrm{a} \propto \mathrm{m}a∝m
a∝1 m2a \propto \frac{1}{\mathrm{~m}^{2}}a∝ m21
a∝m2a \propto m^{2}a∝m2