The gametophyte is not an independent,free-living generation in

If $\alpha$ and $\beta$ are the roots of the equation $ax^2+bx+c=0$ and the equation having roots $\frac{1-\alpha}{\alpha}$ and $\frac{1-\beta}{\beta}$ is $px^2+qx+r=0$,then $r=$

In a stratified cambium,the fusiform initials are

Which one of the following compounds gives aspirin on reacting with acetic anhydride in the presence of conc. $H_2SO_4$?

The hydride ion $H^{-}$ is a stronger base than the hydroxide ion $OH^{-}$. If sodium hydride $(NaH)$ is dissolved in water,which of the following reactions will occur?

At a given instant of time,two particles have position vectors $4 \hat{i} + 4 \hat{j} + 57 \hat{k} \text{ m}$ and $2 \hat{i} + 2 \hat{j} + 5 \hat{k} \text{ m}$ respectively. If the velocity of the first particle is $0.4 \hat{i} \text{ ms}^{-1}$,what is the velocity of the second particle in $\text{ms}^{-1}$ if they collide after $10 \text{ s}$?