Which of the following ligands is expected to be bidentate?

The angle between the lines $x \cos \alpha_1 + y \sin \alpha_1 = p_1$ and $x \cos \alpha_2 + y \sin \alpha_2 = p_2$ is:

If the lines $4x + 3y - 1 = 0$,$x - y + 5 = 0$,and $kx + 5y - 3 = 0$ are concurrent,then $k$ is equal to:

If $\theta$ is the angle between the curves $xy=2$ and $x^2+4y=0$,then $\tan \theta$ is equal to:

The minimum number of times a fair coin needs to be tossed,so that the probability of getting at least two heads is at least $0.96$ is

Four point positive charges of same magnitude $Q$ are placed at four corners of a rigid square frame of side length $L$ as shown in the figure. The plane of the frame is perpendicular to the $Z$-axis. If a negative point charge $-q$ is placed at a distance $z$ away from the centre along the axis $(z << L)$, then: