Student ID number at a certain University are made up of a letter, followed by six 1-digit numbers, and then another letter (example: L 1323 89M). How many student ID numbers are possible if the letters cannot be repeated?

27= -3nso c would be the correct answer. the reason for this is that they are saying a product, showing that this is multiplication; this gives you a reason to cross out a. then, they are saying a number and negative three, so you see they are going to be together; this gives you a reason to cross out d. (-3 and the number are not together) and gives you a reason to cross out b., as they are not together as well.