Answer:
[tex]\fbox {F: +3C, G: +3C}[/tex]
Explanation:
When two conducting spheres come in contact, their charges will become the mean of their charges. This takes place by the transfer of charges from the greater charged sphere to the lesser charged one.
Then :
⇒ F + G / 2
⇒ -14 + 20 / 2
⇒ 6/2
⇒ 3C
∴ Hence, both sphere F and sphere G will have a charge of +3 C.