The floral formula (image) is that of

On electrolysis of aqueous solution of $KI$ in presence of platinum electrodes,which of the following statements are correct?
$(a)$ Hydrogen gas is released at cathode
$(b)$ Oxygen gas is released at anode
$(c)$ $pOH$ of solution decreases
$(d)$ There is deposition of potassium at cathode

The quadratic equation whose roots are $\sin ^2 18^{\circ}$ and $\cos ^2 36^{\circ}$ is :

The contrapositive of the statement "If two numbers are not equal,then their squares are not equal" is

How is the rate of an enzymatic reaction increased?

Two adjacent sides of a parallelogram $ABCD$ are given by $\overline{AB}=2 \hat{i}+10 \hat{j}+11 \hat{k}$ and $\overline{AD}=-\hat{i}+2 \hat{j}+2 \hat{k}$. The side $AD$ is rotated by an acute angle $\alpha$ in the plane of the parallelogram so that $AD$ becomes $AD^{\prime}$. If $AD^{\prime}$ makes a right angle with side $AB$,then the cosine of the angle $\alpha$ is given by