IUPAC name of the compound

Dissociation constant and degree of dissociation of weak acid are $1.8 \times 10^{-5}$ and 0.03 respectively. What will be the concentration of solution of weak acid?

The decreasing order of reactivity of following alcohols with halo acid is

(I) $\mathrm{CH}_3 \mathrm{OH}$

(II) $\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{OH}$

(III)

(IV)

What is the product obtained in the reaction?

$\mathrm{CH}_3-\mathrm{CH}=\mathrm{CH}-\mathrm{CH}_2-\mathrm{CHO} \xrightarrow[\text { (i) } \mathrm{H}_3 \mathrm{O}^{+}]{\text {(i) } \mathrm{LAH}_4}$ product