The area of the plates of a parallel plate capacitor is $A$ and the distance between the plates is $10\,mm$. There are two dielectric sheets in it,one of dielectric constant $10$ and thickness $6\,mm$ and the other of dielectric constant $5$ and thickness $4\,mm$. The capacity of the capacitor is

• A
  $\frac{12}{35}{\varepsilon _0}A$
• B
  $\frac{2}{3}{\varepsilon _0}A$
• C
  $\frac{5000}{7}{\varepsilon _0}A$
• D
  $1500\,{\varepsilon _0}A$