Which of the following halides does not undergo hydrolysis?

An electric fan has blades of length $30 \, cm$ as measured from the axis of rotation. If the fan is rotating at $1200 \, r.p.m.$,the acceleration of a point on the tip of the blade is approximately ........ $m/s^2$.

The obtuse angle between the lines $y = -2$ and $y = x + 2$ is ....$^o$

Fight-or-flight reactions cause activation of

Which valve is located between the right atrium and the right ventricle?

Two persons $A$ and $B$ are located in the $X-Y$ plane at the points $(0,0)$ and $(0,10)$ respectively. (The distances are measured in $MKS$ units). At time $t=0$,they start moving simultaneously with velocities $\overrightarrow{v}_A = 2\hat{j} \text{ m/s}$ and $\overrightarrow{v}_B = 2\hat{i} \text{ m/s}$ respectively. The time after which $A$ and $B$ are at their closest distance is