Decimal representation of a rational number cannot be

Classify the following numbers as rational or irrational with justification:

$(i)$ $-\sqrt{0.4}$

$(ii)$ $\frac{\sqrt{12}}{\sqrt{75}}$

For each question, select the proper option from four options given, to make the statement true : (Final answer only)

$\left(5^{-2}\right)^{3}=\ldots \ldots \ldots$

State whether the following statements are true or false

Every whole number is an integer.

Represent geometrically numbers on the number line:

$\sqrt{5.6}$

Insert a rational number and an irrational number between the following:

$\sqrt{2}$ and $\sqrt{3}$