State whether the following statements are true or false:
$(i)$ Higher the ionization enthalpy,lower the screening effect.
$(ii)$ The ionization enthalpy of $Be$ is higher than that of $B$.
$(iii)$ The shielding effect increases as we move from left to right in a period.
$(iv)$ The increasing order of the first ionization energy is $B < Be < O < N$.

(A) $(i)$ True. Higher ionization enthalpy implies stronger nuclear attraction,which is often associated with a lower screening effect.
$(ii)$ True. $Be$ $(1s^2 2s^2)$ has a fully filled $2s$ orbital,which is more stable than the $2p^1$ configuration of $B$.
$(iii)$ False. The shielding effect remains approximately constant as we move across a period because electrons are added to the same shell.
$(iv)$ True. The order $B < Be < O < N$ is correct due to the stability of fully filled and half-filled orbitals.