D
Giddy UP!!!!!!!!!!!!!!!!!!!!!
Answer:
As the vibrations of the particles reach your ear, your ear drum receives the vibrations which the brain then interprets as sound. In the vacuum of space, there are no (or very, very few) particles to vibrate, so sound cannot travel through this medium.
Explanation:
We know average speed =total distance/time taken
So avg speed=(85+63)/(5+5)=14.8km/hr
relation between potential difference and electric field is given as

so here we know that
d = 3 cm



So now when plates are separated to 4 cm distance carefully
the potential difference between them will change but the electric field between them will remain constant
So at distance of 4 cm also the electric field will be E = 1000 N/C