Total number of nucleophiles from the following is :

Given below are two statements:

Statement I: and are isomeric compounds.

Statement II: and are functional group isomers.

In the light of the above statements, choose the correct answer from the options given below:

The correct order of stability of following carbocations is :

In the given structure, number of sp and $\mathrm{sp}^2$ hybridized carbon atoms present respectively are :