$ACTH$ is secreted by

Selection is a method related to which of the following?

Two ions having masses in the ratio $1: 1$ and charges $1: 2$ are projected into a uniform magnetic field perpendicular to the field with speeds in the ratio $2: 3$. The ratio of the radii of circular paths along which the two particles move is :

The most abundant prokaryotes helpful to humans in making curd from milk and in the production of antibiotics are the ones categorized as:

The number of five-digit numbers divisible by $5$ that can be formed using the digits $0, 1, 2, 3, 4, 5$ without repetition is:

If the plane $3x - 2y - z - 18 = 0$ meets the coordinate axes at $A$, $B$, and $C$, then the centroid of $\triangle ABC$ is: