Effective nuclear charge is maximum in case of

How does the orbital energy change as the nuclear charge increases from $Ne$ to $Ca$?

The unpaired electrons in $Al$ and $Si$ are present in the $3p$ orbital. Which electrons will experience more effective nuclear charge from the nucleus?

The bromine atom possesses $35$ electrons. It contains $6$ electrons in $2p$ orbital,$6$ electrons in $3p$ orbital and $5$ electrons in $4p$ orbital. Which of these electrons experiences the lowest effective nuclear charge?

Which of the following statements is incorrect?

Explain the shielding effect with an example. Also,explain the $2s-2p$ approach in a group and a period.