How many 5 digit codes are possible if the first digit cannot be 0 and digits can be repeated?

Step-by-step explanation:

Zip codes with 5 digits (all five digits can be repeated) : 10^5=100,000 if first digit is 0, its no longer 5-digit right? Zip codes with no digit being repeated: 10*9*8*7*6=30,240 if first digit is 0, its no longer 5-digit right? Zip codes with at least one digit being repeated: 90000-27216 = 62784? N