Portland cement is manufactured using which of the following?

Despite being multicellular,its cells are not organized into tissues.

Three identical square plates rotate about the axes shown in the figure in such a way that their kinetic energies are equal. Each of the rotation axes passes through the centre of the square. Then the ratio of angular speeds $\omega _1 : \omega _2 : \omega _3$ is

If the two circles $2x^2 + 2y^2 - 3x + 6y + k = 0$ and $x^2 + y^2 - 4x + 10y + 16 = 0$ cut orthogonally,then the value of $k$ is

The reaction of ethyl methyl ketone with $Cl_2$ in the presence of excess $OH^-$ gives the following major product:

If $\frac{4 + 3\sqrt{3}}{\sqrt{7 + 4\sqrt{3}}} = a + \sqrt{b}$,then $(a, b) = $