A valid password on a Web site contains 3 letters (A-Z, 26 total), followed by 3 digits (0-9). Letters and numbers can be repeated. The number of possible passwords equals _____.
A. 26*25*24+10*9*8
B. 26^3+10^3
C. 26^3*10^3
D.26*25*24*10*9*8
1 answer