Excess of which of the following in water causes blue baby syndrome disease?

Lactose is a disaccharide of

If $^nC_r$ denotes the number of combinations of $n$ things taken $r$ at a time,then the expression $^nC_{r+1} + ^nC_{r-1} + 2 \times ^nC_r$ equals

In the following common emitter circuit,if $\beta = 100, V_{CE} = 7 \, V, V_{BE} = 0 \, V$ (negligible),and $R_C = 2 \, k\Omega$,then find $I_B$ in $mA$.

$Mg$ is obtained by

The plank in the figure moves a distance $100\,mm$ to the right while the centre of mass of the sphere of radius $150\,mm$ moves a distance $75\,mm$ to the left. The angular displacement of the sphere (in radian) is (there is no slipping anywhere):-