Given variable costs of $$\frac{94}{?}$ unit, fixed costs of $$4,900$ and a contribution margin of

$$\frac{60}{?}$ unit, the contribution margin ratio $($to $2$ decimal places$)$ is

a$.1\mathrm{.}76$

b$.0\mathrm{.}01$

c$.0\mathrm{.}64$

d$.0\mathrm{.}39$