Connect thank you so much.

Connect if we reverse edges for number 2 vertex, so we should reverse

1. vertex1 --> vertex2, so it will be vertex2 --> vertex1

2. vertex2 --> vertex3, so it will bevertex3 --> vetex2

3. vertex2 --> vertex4, so it will bevertex4 --> vertex2

is this correct?

what numbers is test 3 please could someone tell me?

what does it mean "uninterrupted water supply throughout the city" ?

please could someone explain first example? which vertex edges they reversed???