6) How many different 5-digits zip codes can we have?
A) 100,000 B) 90,000 C) 81,000 D) 80,000
7) How many different 5-digits zip codes can we have with no
zero as the first digit?
A) 100,000 B) 90,000 C) 81,000 D) 80,000
8) How many different 5-digits zip codes can we have with no
zero as the first and last digit?
A) 100,000 B) 90,000 C) 81,000 D) 80,000
9) A security code consists of 4 parts, two digits...