[wednesday quiz] back in harness

1. What is the area of A-0 paper, in metric?

2. Did the first traffic lights appear in New York, Detroit or Hamburg, in 1919?

3. What is digamy?

4. In Roman numerals, what is the letter M with a bar over it?

5. Which was the first credit card?

Answers

One square metre, Detroit, a second legal marriage, one million, Diner's Club