Fusion reaction takes place at high temperature because

The substance used in the thermite process of reducing metal ores is

The general solution of the differential equation $\frac{y dx - x dy}{y} = 0$ is . . . . . . .

For any $y \in R$,let $\cot ^{-1}(y) \in (0, \pi)$ and $\tan ^{-1}(y) \in \left(-\frac{\pi}{2}, \frac{\pi}{2}\right)$. Then the sum of all the solutions of the equation $\tan ^{-1}\left(\frac{6 y}{9-y^2}\right)+\cot ^{-1}\left(\frac{9-y^2}{6 y}\right)=\frac{2 \pi}{3}$ for $0 < |y| < 3$,is equal to

The currents $i_1$ and $i_2$ through the resistors $R_1 = 10\,\Omega$ and $R_2 = 30\,\Omega$ in the circuit diagram with $E_1 = 3\,V$,$E_2 = 3\,V$,and $E_3 = 2\,V$ are respectively:

$4 \ g$ of a hydrocarbon on complete combustion gave $12.571 \ g$ of $CO_2$ and $5.143 \ g$ of water. What is the empirical formula of the hydrocarbon?