The chlorination of ethane is an example of which of the following types of reactions?

Which of the following plants are used as green manure in crop fields and in sandy soils?

Which part of the human brain controls the breathing movements?

$A$ particle of mass $m$ and charge $q$ moves with a constant velocity $v$ along the positive $x$-direction. It enters a region containing a uniform magnetic field $B$ directed along the negative $z$-direction,extending from $x = a$ to $x = b$. The minimum value of $v$ required so that the particle can just enter the region $x > b$ is

$\int \frac{x-1}{(x+1) \sqrt{x(x^2+x+1)}} dx = $

The approximate atomic weight of an element is $26.89$. If its equivalent weight is $8.9$,the exact atomic weight of the element would be: