Which of the following is not an ore of magnesium?

The path of a projectile is given by the equation $y = ax - bx^2$,where $a$ and $b$ are constants and $x$ and $y$ are respectively horizontal and vertical distances of the projectile from the point of projection. The maximum height attained by the projectile and the angle of projection are respectively:

In the brown ring complex $[Fe(H_2O)_5NO]SO_4$,the primary valency (oxidation state) of $Fe$ is:

$ABC$ is a triangular plate of uniform thickness. The sides are in the ratio $3:4:5$ as shown in the figure. $I_{AB}, I_{BC}, I_{CA}$ are the moments of inertia of the plate about axes $AB, BC$ and $CA$ respectively. Which one of the following relations is correct?

What product is obtained when ethyl hydrogen sulphate is heated with an excess of alcohol at $410 \, K$?

The equation of the locus of $z$ such that $\left|\frac{z-i}{z+i}\right|=2$,where $z=x+iy$ is a complex number,is