Serial numbers for a product are to be made using 2 letters followed by 4 digits. The letters are to be taken from the first 6 letters of the...

Serial numbers for a product are to be made using 2 letters followed by 4 digits. The letters are to be taken from the first 6 letters of the alphabet, with no repeats. The digits are taken from the 10 digits (0,1,2,3,4,5,6,7,8,9) with no repeats. How many serial numbers can be generated?