...And other moronic questions asked in interviews.

If you go on a tech interview and the moron on the other side of the table asks you, "Why are manhole covers round?" You can now safely answer the question with the epiphet, "You're a moron!"

These examples of "Round" manhole covers come from Kendal in Cumbria, England.

Square manhole with diagonally bisected cover

Rectangular manhole with three square covers. BT, I think.

Square manhole with diagonally bisected cover... and very securely attached with macadam