I'm certainly no expert but, as at this stage, thay have only asked if you have any questions
it may be best to start with a question rather than what sounds like the kind of formal opening statement you would make on your application. Though you could sneek in the responsibility bit after the question. I think I would probably remove the reference to you having been unsuccessful with your training application as it perhaps makes a negative impact. Perhaps use the term "haven't had the opportunity yet" instead.
(Cave Duck, Thu 22 Apr 2010, 11:53, Reply)