What is the largest 5-digit number with unique digits?

Q. What is the smallest 3-digit number with unique digits?

Q. What is the largest six-digit number that can be formed with the digits 3, 5, 7, 0, 4, and 2 using each digit only once?

Q. What would you get when the sum of largest 4-digit number and the smallest 5-digit number is added to the difference of the smallest 6-digit number and the largest 5-digit number?

Q. What is the largest number that can be formed with the digits 2, 4 and 5?

Q. What is the largest $5$ digit number possible?