Running out of Oil
When will we run out of oil? In the 1970s, it was predicted that oil wells would run dry by the year 2000, but new reserves were discovered. So in this week's Question we find out how long we have left, and if rising oil prices will make difficult reserves more productive. Also we ask how the Olympic torch stays lit in flight, and why do earplugs keep outside noises out, but make internal noises unbearably loud?