How many such digits are there in the number $52361984$ each of which is as far away from the beginning of the number as when the digits are rearranged in ascending order within the number?

Choose the correct alternative to complete the series: $aa . . ab . . . . . . aaa . . . a$.

Fill in the blank space for the given series with the correct alternative.
$17, 19, 23, 29, (...), 37$

Fill in the blank space for the given series with the correct alternative.
$19, 2, 38, 3, 114, 4, (...)$

The following questions are based on the five three-digit numbers given below:
$972, 526, 487, 359, 251$
If the positions of the digits of each of the numbers are interchanged such that the first digit becomes the second,the second digit becomes the third,and the third digit becomes the first,which of the following will be the highest?

Choose the correct alternative to complete the series: $ab .... ...b .... ....bbaa$