The figure shows three long straight wires $P, Q$ and $R$ carrying currents normal to the plane of the paper. All three currents have the same magnitude. Which arrow best shows the direction of the resultant force on the wire $P$?

$\frac{\sqrt{8+\sqrt{28}}+\sqrt{8-\sqrt{28}}}{\sqrt{8+\sqrt{28}}-\sqrt{8-\sqrt{28}}}$ is equal to

$\frac{1}{e^{3x}}(e^x + e^{5x}) = a_0 + a_1x + a_2x^2 + \ldots$
$\Rightarrow 2a_1 + 2^3a_3 + 2^5a_5 + \ldots$ is equal to

Let $I$ be the moment of inertia of a uniform square plate about an axis $AB$ passing through its center and parallel to two of its sides. $CD$ is an axis in the plane of the square and passing through the center,making an angle $\theta$ with $AB$. The moment of inertia of the plate about the axis $CD$ is:

Which of the following pairs are isoelectronic and isostructural? $NO_3^-, CO_3^{2-}, ClO_3^-, SO_3$

Which of the following is a transparent tissue?