Please help me with this

Classify each statement about effective nuclear charge, zeff, as true or false.

Between 2014 and 2016, more than 25,000 children in flint, michigan, drank water that was contaminated with lead from lead pipes. during this time, the city claimed the water was safe to drink. which of these actions could the city have taken to ensure that the drinking water was free from lead?

Which other elements contain the same number of outer electrons as sodium