"Do you know?" and Others

"One One Thousand" -- What to Do? Reading "Do you know?" and Others 1 minute Next The "Hard C" Sound

When a question like "Do you know?" or "Do you recall?" is tacked on at the end of
another question, use an interrog for both questions.

...How close were you to the edge of the road? Do you know?
...What time was it that he arrived? Do you remember?
...Where was he stationed? Do you recall?

Happy punctuating!