Which of the following has the minimum bond length?

$N_2$ and $O_2$ are converted into monoanions $N_2^-$ and $O_2^-$ respectively. Which of the following statements is wrong?

The bond order of $He_2^+$ molecule ion is

In which of the following ionization processes has the bond energy increased and the magnetic behaviour changed from paramagnetic to diamagnetic?

Which one of the following sketches is not correctly matched?

The molecular orbital configuration of a diatomic molecule is
$\sigma 1s^2 \sigma^* 1s^2 \sigma 2s^2 \sigma^* 2s^2 \sigma 2p_x^2 \pi 2p_y^2 \pi 2p_z^2$
Its bond order is