Explain the delocalization of electrons in $CH_3-CH_2^+$ and $CH_3-CH=CH_2$.

(N/A) In $CH_3-CH_2^+$,the $\sigma$-orbital of the $C-H$ bond of the $CH_3$ group and the vacant $2p$-orbital of the $CH_2^+$ group are parallel,which allows for the delocalization of $\sigma$-electrons into the vacant $p$-orbital (hyperconjugation).
In $CH_3-CH=CH_2$,the $\sigma$-orbital of the $C-H$ bond of the $CH_3$ group and the $2p$-orbitals of the $\pi$-bond of the $CH=CH_2$ group are parallel,allowing for the delocalization of $\sigma$-electrons into the $\pi$-system (hyperconjugation).