To which family does $Ricinus$ $communis$ belong?

$\left(\frac{1+i}{1-i}\right)^4+\left(\frac{1-i}{1+i}\right)^4$ is equal to

The coefficient of $x^5$ in the expansion of $(1 + x)^{21} + (1 + x)^{22} + \dots + (1 + x)^{30}$ is

The effective atomic number $(EAN)$ of $Co(CO)_4$ is $35$,hence it is less stable. It attains stability by:

The potential difference between two parallel plates is $10^4 ~V$. If the plates are separated by $0.5 ~cm$,the force on an electron between the plates is

Which of the following is a pseudocereal?