Try to be sure that the answer you offer closely correlates
with the environment at the company you're interviewing
with. If it does not, the interviewer may wonder if
you'll be satisfied or happy with the position.
Be realistic. If you have many family commitments, 100% would
probably not be reasonable. Try to find out how much travel
time is usual BEFORE going into the interview.
This is a perfectly legal question for the potential
employer to ask. If your answer is no, assure the employer
that you are legally entitled to work in this country.
If you cannot or do not want to work overtime, and the
position you are interviewing for requires overtime, perhaps
the position is not for you. However, you should realize
that most management positions, which many people think are
9 to 5, really involve more hours than 40 in a week.
This question may be used to discriminate against you --
to determine if you have children or parents that would
take time away from your job. Answer honestly, but briefly.
Of course, the "best" answer is that you have a perfect
attendance record. If this is not true for you, do not answer
this way.
Elaborate. If the job requires that you drive your own or a
company vehicle, your answer should be "yes." If it does
not, assure the interviewer that you'd have no problems
getting to and from work.
Elaborate. If your answer is "no," you should have a great
reason for refusing. This refusal may disqualify you from
further consideration.