Which of the following is a property of water?
-it has a low boiling point.
-a meniscus forms when placed in glass,
-it is nonpolar.
-it does not have a surface tension,

The problem here is that according to aufbau principle before 3d orbital 4s subshell comes.after filling 3p orbital with electrons you have 4 electrons left, you place two in 4s with opposite spin and the other two in 3d in any of its two orbitals of total five orbitals with the same spin.