Kingfisher company plans to assign identification numbers to its employees. Each number is to consist of four different digits from 0 to 9, inclusive, except that the first digit cannot be 0. How many different identification numbers are possible?  Choose the correct answer.
A) 3,024  B) 4,536  C) 5,040  D) 9,000  E) 10,000
Kingfisher company plans to assign identification numbers to its employees.The first digit can take 9 values from 1 to 9 inclusive;   The second digit can also take 9 values (9 digits minus the one we used for the first digit plus 0);   The third digit can take 8 values;   The fourth digit can take 7 values.   Total = 9*9*8*7 = something with the units digit if 6.   Answer: 4,536.
<result>B</result>
Kingfisher company plans to assign identification numbers to its employees. Each number is to consist of four different digits from 0 to 9, inclusive, except that the first digit cannot be 0. How many different identification numbers are possible?