Find the least number that must be subtracted from the following number to make them a perfect square,

$5045$

Find the least number which must be subtracted from $18265$ so as to get perfect square. Also, find the square root of the perfect square so obtained.

Find the least number that must be subtracted from the following number to make them a perfect square,

$194491$

Find the least number which must be subtracted from $26535$ so as to get perfect square. Also, find the square root of the perfect square so obtained.

Simplify the following and write in the form of $\frac{p}{q}$.

$\sqrt{\frac{16}{25}}$

Simplify the following and write in the form of $\frac{p}{q}$.

$\sqrt{6\frac{1}{4}}$