The key answer of exercise 1

a)

1. one
2. one hundred
3. twenty
4. fifty
5. five
6. ten

b)

1. euros
2. pounds
3. dollars
4. pence / p
5. euros
6. pounds

c)

1. forty-five pounds
2. fifteen pounds
3. fifty-nine euros
4. ninety-nine pence / p
5. one dollar eighty-nine
6. seven euros twenty-five
7. four pounds seventy
8. nineteen dollars eighty-five