An oscillator is nothing but an amplifier with

If $y = 4x - 5$ is tangent to the curve $y^2 = px^3 + q$ at $(2, 3)$,then

$Fe$ is made passive by

$2 \tanh^{-1} \frac{1}{2}$ is equal to

Which of the following statements are correct for alkali metal compounds?
$(i)$ Superoxides are paramagnetic in nature.
$(ii)$ The basic strengths of hydroxides increase down the group.
$(iii)$ The conductivity of chlorides in their aqueous solutions decreases down the group.
$(iv)$ The basic nature of carbonates in aqueous solutions is due to cationic hydrolysis.

$\int_0^2 \frac{2x-2}{2x-x^2} dx$ is equal to