Which of the following is/are correct statement:

The correct heat of hydrogenation order is

$\left(p\right)1,3-$ Pentadiene

$\left(q\right) 1, 3-$Butadiene

$\left(r\right) 2,3-$ dimethyl $-1,3-$butadiene

$\left(s\right)$ Propadiene

Arrange the following carbanions in decreasing order of stability:

$\left(\mathrm{I}\right) {}^{⊝}\mathrm{CH}_2-\mathrm{Cl}$

$\left(\mathrm{II}\right) {}^{⊝}\mathrm{CH}_2-\mathrm{CN}$

$\left(\mathrm{III}\right) {}^{⊝}\mathrm{CH}_2-{\mathrm{NO}}_2$

$\left(\mathrm{IV}\right) {}^{⊝}\mathrm{CH}_2-{\mathrm{CH}}_3$

The following carbocation rearranges to:

The order of basic strength of the given basic nitrogen atoms is: