Which of the following is not an ore of magnesium?

If the length of a stretched string is shortened by $x \%$ and the tension is increased by $44 \%$,then the ratio of the final and initial fundamental frequencies is $2:1$. The value of $x$ is:

If the bisectors of the pair of lines $x^2-2 m x y-y^2=0$ are represented by $x^2-2 n x y-y^2=0$,then

List the changes observed in an angiosperm flower subsequent to pollination and fertilisation.

Identify the major product formed when $2-$Methylhexan$-3-$ol is heated with concentrated sulphuric acid.

Two spheres each of mass $M$ and radius $\frac{R}{2}$ are connected at their centres with a massless rod of length $2R$. What will be the moment of inertia of the system about an axis passing through the centre of one of the spheres and perpendicular to the rod?