How many whole numbers are there with not more than 4 digits? i thought the answer is 9999, but it apparently isn'

We need to find whole numbers  not more than 4 digits

Not more than 4 digits means it can be a one digit, 2 digit, 3 digit and a 4 digit number

It is a whole number so we include 0

, , ,  

First digit  we can use numbers 0  to 9 so 10

For second digit we can use numbers 0 to 9 so 10

For third digit we can use numbers 0 to 9 so 10

For fourth digit we can use numbers 0 to 9 so 10

---10--, ---10 , --10,  10

So 10* 10 * 10 * 10 = 10000

10000 whole numbers are there with not more than 4 digits

not sure but it may be b, as i said i'm not sure.