Here are the answers based on your questions:
Question 1: How do you say "How old are they?"
- Correct answer: Quel âge ont-elles?
Question 2: Which number should come next? onze, douze, ____
- Correct answer: treize
Question 3: How do you say "How old are you?" in French?
- Correct answer: Quel âge avez-vous?
Question 4: Which expression means "She is twelve years old"?
- Correct answer: Elle a douze ans.
Question 5: Which number is thirty-one in French?
- Correct answer: trente-et-un
If you have any more questions or need further assistance, feel free to ask!