An easy one to go with the Christmas celebrations and to kill the digestive time under the festively decorated needle tree: What’s the x standing for?
The answer to last month’s riddle: who killed the scientist? Gabi and Felice, obviously, if you know your periodic table of elements: 31 => (Ga)llium; 83 => (Bi)smuth; 26 => (Fe)rrum; 3 => (Li)thium; 58 => (Ce)sium.
See all riddles on http://blogs.exeter.ac.uk/xm2news/category/riddles/.