The formation of which of the following polymers involves a hydrolysis reaction?

If $f(x) = \frac{x^2}{x+a}$, then $f^{\prime \prime}(a)$ is equal to

If the voltage between the terminals $A$ and $B$ is $17\,V$ and the Zener breakdown voltage is $9\,V$,then the potential across $R$ is....$V$

Vitamin $K$ is required for:

If $3x^2-11xy+10y^2-7x+13y+k=0$ denotes a pair of straight lines,then the point of intersection of the lines is

If $f: R \rightarrow R$ is defined by $f(x) = x - [x]$,where $[x]$ is the greatest integer not exceeding $x$,then the set of points of discontinuity of $f$ is