Mystery #2Tier 2crowds and spread
Why does illness race through a packed school or busy city so quickly?
Notice how a cold seems to tear through a packed classroom, while the same week the quiet house next door stays perfectly well. Same germ, wildly different speed. What is it about a crowd that lets an illness spread so much faster?
Your guess
Why do you reckon a germ spreads so much faster when lots of people are packed together?
There's no single magic word to type, have a go in your own words, then reveal the answer to see how close you got.
Make a guess to unlock the hints and the answer.