Best wishes to Valed for his retirement. I know I've certainly appreciated his good humour and candour over the past year of writing here. Always to the point but always encouraging and thoughtful. Thanks too for 'Maths Answers', what a great contribution to share. I love the bits on the slides that say to the pupils 'any problems, please ask!': seems obvious but a nice touch. All the best, and I hope you will continue to post from time to time.