The last digit of $5^{25}$ is .......

For any positive integer $n$,the last digit of $5^n$ is always.......

The difference between the $HCF$ and $LCM$ of two prime numbers $7$ and $11$ is . . . . . . .

Match the following items:

$Q.1.$ $HCF$ of $8$ and $6$	$A. 49$
$Q.2.$ $LCM$ of $(26, 91)$	$B. 182$
	$C. 2$

What type of decimal expansion is $0.9999...$? (Terminating,Non-terminating repeating,Non-terminating non-repeating)

Find the $HCF(510, 92)$.