28. In a certain city, the online selection rule for motor vehicle license plate codes is: the last five positions of the license plate must contain two English letters (where the letters $I$, $O$ are not allowed) and the last position must be a digit. How many codes meet this regulation?
28. The online selection rule for motor vehicle license plates in a certain city is: the last five positions of the license plate must contain two English letters (where the letters $I$, $O$ are not allowed) and the last position must be a digit. How many codes meet this requirement?
【Analysis】According to the problem, there are $26-2=24$ available English letters, and these letters can only appear in two of the first four positions, while the remaining two positions and the fifth position must be digits. Using the multiplication principle, we can derive the conclusion.
【Solution】According to the problem, there are $26-2=24$ available English letters, and these letters can only appear in two of the first four positions, while the remaining two positions and the fifth position must be digits.
The two letters occupy 2 out of the first 4 positions, with a total of 6 methods. Each letter has 24 options, and the remaining 3 positions are digits, each with 10 options. Therefore, the number of codes that meet the requirement is $6 \times 24 \times 24 \times 10 \times 10 \times 10=345600$. Answer: There are 345600 codes that meet the requirement.