How many of the following statements are correct? Based on Mo-Theory.

a) In the formation of $N_2^{\oplus }$ from $N_2$ the electron is removed from $\pi 2p_y\text{ (q) }\pi 2p_x$

b) In the formation of $\stackrel{\oplus }{C}O$ from "CO"  the electron is removed from $\sigma 2s$

c) In ${\mathrm{O}}_2-$ molecule HOMO is $\pi 2P_x\mathrm{\&}\pi 2p_y$ and LUMO is $\sigma 2p_z$

d) $C_2$ molecule has only $\pi -$ bonds

e) $H_2^{2-}$ Ion formation is not feasible

f) Bond order of $\stackrel{\oplus }{C}O$molecular ion is 3.5

g) During the formation of ${\stackrel{\oplus }{O}}_2$ from $O_2$ bond length of ' O -O" decreases.

h) During the formation of ${\stackrel{\oplus }{N}}_2$ from  "$N_2$" its bond length increases.