The gap between the plates of a parallel$-$plate capacitor is filled with three equal$-$thickness layers of mica, paper, and a material of unknown dielectric constant. The area of each plate is $120$ cm$2$ and the capacitor$$s gap width is $3\mathrm{.}75$ mm$.$ The values of the known dielectric constants are Kmica $=5\mathrm{.}5$ and Kpaper $=3\mathrm{.}25.$ The capacitance is measured and found to be $95$ pF$.$