20. which of the following statements is an accurate description of sound transmission through various mediums? a. sound insulators prevent sound from being transmitted better than elastic solids. b. gases conduct sound better than liquids. c. inelastic materials conduct sound better than elastic solids. d. elastic solids prevent sound from being transmitted better than liquids.

The electric field between square plates of a parallel-plate capacitor has magnitude e. the potential across the plates is maintained with constant voltage by a battery as they are pulled apart to twice their original separation, which is small compared to the dimensions of the plates. the magnitude of the electric field between the plates is now equal to a)e b)e/4 c)e/2 d)4e e)2e