Fill in the blank with a word/ phrase in the box (self-driving, planets, different, flying cars, friendly, traffic jams, run on, planets)

fill in the blank with a word/ phrase in the box
(self-driving, planets, different, flying cars, friendly, traffic jams, run on, planets)
in 100 years everything will be very (1) ........... . instead of using regular cars, we will use (2) ............ . they will take us to everywhere we like, even other (3) ........... .
these cars will (4) ............ water so they are (5) ........... to the environment. they will be (6) ............ without driver intervention. the only thing we need to do is to inform the flying cars where the (7) ........... is and then the flying car will do the rest. the cars will be much faster, safer and there will be no (8) ............ because each flying car has its own way.
will you know what will happen in the future? no one really knows, but to think about an indefinite future is very interesting