Semi-water gas is a mixture of which of the following?

In the circuit shown below $E_1 = 4.0 \, V$,$R_1 = 2 \, \Omega$,$E_2 = 6.0 \, V$,$R_2 = 4 \, \Omega$ and $R_3 = 2 \, \Omega$. The current $I_1$ is ............... $A$

The vectors $3\,i + j - 5\,k$ and $a\,i + b\,j - 15\,k$ are collinear,if

The bond energy of $Cl_2$,$Br_2$,and $I_2$ follows the order:

$\int \frac{dx}{\cos x \sqrt{\cos 2x}} =$

The density of water at $20^oC$ is $0.998 \ g/cm^3$ and at $40^oC$ is $0.992 \ g/cm^3$. The mean coefficient of cubical expansion (in per ${}^oC$) is