Breeding of crops with high levels of minerals,vitamins,and proteins is called:

Parts $A, B, C$ and $D$ of the human eye are shown in the diagram. Select the option which gives correct identification along with its functions / characteristics:

$A$ thin rod of length $L$ is bent to form a semicircle. The mass of the rod is $M$. What will be the gravitational potential at the centre of the circle?

If the direction ratios of two lines are given by $3lm - 4ln + mn = 0$ and $l + 2m + 3n = 0$,then the angle between the lines is:

The logic gate equivalent to the circuit shown in the figure is

Explain why $BeH_{2}$ molecule has a zero dipole moment although the $Be-H$ bonds are polar.