Here's a really tough challenge for you. One of these two pictures shows me standing beside the mighty River Mississippi in New Orleans. The other shows me standing beside the mighty River Trent near my home here in Nottingham, England. Can you figure out which is which?
And while we're on the subject of spotting differences, can you detect any difference between the melodies of 'If You Don't Want Me, Please Don't Dog Me Around' and 'Make Me A Pallet On Your Floor'? You can hear them in these two videos.