The back pages Puzzles

摘要

1 The structure of which substance allegedly came to chemist August Kekule during a dream of a snake biting its tail? 2 What might you measure using a Wheatstone bridge? 3 What form of pneumonia, usually caused by contaminated water, was first identified in an outbreak at a Philadelphia hotel in 1976? 4 What geological era, noted for an explosion in invertebrate life and named after a Welsh Celtic tribe, was sandwiched between the Cambrian and Silurian eras? 5 Io, Europa, Ganymede... what's missing?