Which of the following bonds is the most polar?

Which of the following is not a polyamide?

In $YDSE$,the separation between the slits is halved and the distance between the slit and the screen is doubled. The fringe width is

Given that $a, b \in \{0, 1, 2, \ldots, 9\}$ with $a+b \neq 0$ and that $\left(a+\frac{b}{10}\right)^x = \left(\frac{a}{10}+\frac{b}{100}\right)^y = 1000$. Then,$\frac{1}{x}-\frac{1}{y}$ is equal to

The equivalent capacitance between points $A$ and $B$ of the circuit shown will be

Two point white dots are $1\, mm$ apart on a black paper. They are viewed by an eye with a pupil diameter of $3\, mm$. Approximately,what is the maximum distance in $m$ at which these dots can be resolved by the eye? [Take wavelength of light $\lambda = 500\, nm$]