In order, duck's phases of ending a relationship are:

Duck viewed relationships as a series of events. There are four main phases, in which the perception of the people involved in the relationship changes due to strain from different factors.  The phases are:

1) Intra-psychic phase
The individual does not express dissatisfaction or unhappiness with the relationship yet but feels it.

2) Dyadic phase
Discussion regarding the negative feelings is usually carried out in this phase, and anger and guilt tend to rise.

3) Social phase
The separation of the two individuals is shared socially and both choose their own friends and supports for this phase.

4) Grave-dressing phase
This phase occurs some time after the relationship has ended, and the individuals will look back thinking of all the things they did correctly, while also recollecting the negatives of the other person. Trust in relationships is rebuilt in this phase as the individual becomes ready for a new relationship.

Answer : romans built laws to manage the pollution which was lead by smoke produced by the factories.

they had the law tat factories that produces smoke cannot be built near residential buildings.

building of proper sewage system was done to ensure that the waste is carried away from the humans so that they do not get diseases from it.

also they built water systems to provide water in those areas which are drought prone.