I sent in answers for the senior-E and some of the senior-H for this last one. They're probably wrong but it was fun to attempt. I was given it for years but could never be bothered, but I've actually got good maths teachers now (due to choosing double maths A Level) and I rather enjoyed doing it and I'm enjoying maths more in general. It's great to be given interesting problems, the sort that linger for a while, then you get the answer completely unexpectedly. I love that about maths. They should definitely make it much more widely available. Great fun.