[Grammar] question Formation

[xpert]

They were driving one hundred kilometers an hour.

Which question sounds better?

How many kilometers were they driving?How fast were they driving?

Are there any other possible formations...

Thanks in advance

 

[5jj]

They were driving at one hundred kilometers an hour.

Which question sounds better?

[STRIKE]How many kilometers were they driving[/STRIKE]?

Are there any other possible formations?


How many kilometers an hour were they doing?
How fast were they driving?
What speed were they driving at?

5

 

[xpert]

Thanks a million :up: