The voltage across an air-filled parallel-plate capacitor is measured to be v0 =
. When a dielectric is inserted and completely fills the space between the plates as in Figure P26.44, the voltage drops v1 =
. (a) What is the dielectric constant of the inserted material? (b) Can you identify the dielectric? If so, what is it? (c) If the dielectric does not completely fill the space between the plates, what could you conclude about the voltage across the plates?