What is minimum size of a main conductor from distribution board to water main ?

What is the new height of a light switch supposed to be?

What is minimum size of a main conductor from distribution board to water main?---Depends on the size of the service. In new homes, it is a minimum of 100 Amps.

What is the new height of a light switch supposed to be? No specific height unless locally mandated. Typically they are 48" to the bottom of the box. I believe ADA is 42".