What is the largest single digit prime number?

Q.

What will be the difference between the largest and smallest three digit number made by using distinct single digit prime numbers?

Q.

The largest 2-digit prime number is ___

Q. Which one of the following is the largest prime number of three digits?

Q. What is the GCF of the largest 2-digit prime number and the smallest 2-digit prime number?

Q. Kate is a very curious student, she had something in mind and so she asked Maggie to write the numbers according to the following statements and give the result:
1. Write down the largest 3 digit number using single digit prime numbers (digits should not be repeated).
2. Then write down the smallest 3 digit number using single digit prime numbers (digits should not be repeated).
3. Find the difference.

What answer should Maggie get?