Which of the following figure best represents the variation of magnetic susceptibility ($\chi$) with temperature for a diamagnetic substance?

A wire of length $L$ is bent in the form of a circular coil and current '$i$' is passed through it. This coil is kept in magnetic field. The torque acting on the coil will be maximum, when the number of turns is ___

Two long parallel wires carrying currents $8$A and $15$A in opposite directions are placed at a distance of $7$ cm from each other. A point P is at equidistant from both the wires such that the lines joining the point P to the wires are perpendicular to each other. The magnetic field at P is ___ $\times 10^{-6}$ T. (Given: $\sqrt{2} = 1.4$, $\mu_0 = 4\pi \times 10^{-7}$ SI unit)

A square loop of area $25 \text{ cm}^2$ has a resistance of $10$ $\Omega$. The loop is placed in uniform magnetic field of magnitude $40$ T. The plane of the loop is perpendicular to the magnetic field. The work done in pulling the loop out of the magnetic field slowly and uniformly in one second will be