Consider this radical expression:

$\sqrt{961}+\sqrt{49}$

Indicate if the root is a real number or not. In the case of a real number, evaluate.

Rationalize the denominator of the radical expression.

$\frac{1}{\sqrt{210}}$

Rationalize the denominator of the radical expression.

$\frac{\sqrt7}{\sqrt{37}}$

Rationalize the denominator of the radical expression.

$\frac{\sqrt{31}}{\sqrt{91}}$

Rationalize the denominator of the radical expression.

$\frac{13}{\sqrt{17}-1}$

Rationalize the denominator of the radical expression.

$\frac{10}{\sqrt{11}+\sqrt{21}}$

Rationalize the denominator of the following expression.

$\frac{7-s}{27-2\sqrt{s}}$