Which of the following is a medicinal plant?

The recessive genes located on the $X$-chromosome in humans are always:

$A$ simple harmonic oscillator consists of a particle of mass $m$ and an ideal spring with spring constant $k$. The particle oscillates with a time period $T$. The spring is cut into two equal parts. If one part oscillates with the same particle,the time period will be

$19 \ g$ of a mixture containing $NaHCO_3$ and $Na_2CO_3$ on complete heating liberated $1.12 \ L$ of $CO_2$ at $STP$. The weight of the remaining solid was $15.9 \ g$. What is the weight (in $g$) of $Na_2CO_3$ in the mixture before heating?

The sum of the last eight coefficients in the expansion of $(1 + x)^{15}$ is:

The $[Fe(CN)_6]^{3-}$ complex ion