Each student at a certain business school is assigned a 4-digit studen

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9 10 10 4

9*10*10*4 = 3600.

Just for understanding, If the same question mentioned as no repetition allowed, then it would be

Always start with the most restrictive clause, which number should end with a prime - 4 options are available.
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4

The next restrictive clause is the number should not start with a zero. Already one number has been placed in the unit position and now we cant include zero to. So we have remaining 8 numbers to put in first place.

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8 4

Remaining two positions has not restrictions. Hence we have 8 numbers (including zero) for one position and 7 numbers for the other.

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8 8 7 4

= 8*8*7*4

Using the slot method, there are four choices so four slots.

The first restriction is that the number must not begin with zero, thus 9 choices.
The follow two slots, or digits, do not have restrictions, thus 10 choices each.
The last slot must be a prime number, thus four choices (2,3,5, and 7).

Therefore,
\(9 * 10 * 10 * 4 = 3600\)

There are 9 possible options for the first digit, 10 for the second digit, 10 for the third digit, and 4 for the last digit, since the prime digits are 2, 3, 5, and 7.

Thus, the number of codes that can be created is 9 x 10 x 10 x 4 = 3600.

Answer: B