How many license plates one can create using the LLLDDDD\displaystyle {L}{L}{L}{D}{D}{D}{D} -format in which L\displaystyle {L} stands for any capital letter A-J and D\displaystyle {D} stands for any odd digit?

i. If the repetition of digits and letters is allowed.

ii. If the repetition of digits is allowed but the repetition of letters is not allowed.

iii. If the repetition of digits is not allowed but the repetition of letters is allowed.

iv. If the repetition of digits and letters is not allowed.