What is the correct order of stability of the following carbanion?

(I)    

(II)  

(III)    

(IV)  

What is the order of stability of the following carbocations?

Which of the following intermediate sites have a similar geometry?

$\left(\mathrm{i}\right)$ $\stackrel{+}{\mathrm{C}}{\mathrm{H}}_2{\mathrm{CH}}_3$

$\left(\mathrm{ii}\right)$ $\stackrel{-}{\mathrm{C}}{\mathrm{H}}_2{\mathrm{CH}}_3$

$\left(\mathrm{iii}\right)$ $:\stackrel{-}{\mathrm{C}}{\mathrm{H}}_2{\mathrm{COCH}}_3$

$\left(\mathrm{iv}\right)$ ${\mathrm{CH}}_2=\mathrm{CH}-\stackrel{-}{\mathrm{C}}{\mathrm{H}}_2$

Arrange the homolytic bond energies of $\mathrm{C}-\mathrm{H}$ bond designated by I, II, III and IV. 

The reaction in which free radicals can be formed by homolytic fission is

$\left(\mathrm{a}\right)$  

$\left(\mathrm{b}\right)$  

$\left(\mathrm{c}\right)$  

The correct order of nucleophilicity:

(I) 

(II) ${\mathrm{CH}}_3{\mathrm{O}}^{-}$

(III) ${\mathrm{CN}}^{-}$

IV)