<span>The answer is Ravenna. The city is on a lowland plain close to the union of the Ronco and Montone rivers, 6 miles (10 km) inner from the Adriatic Sea, with which it is linked by a canal. Ravenna was a significant part in history as the principal of the Western Roman Kingdom in the 5th century AD and later (6th–8th century) of Ostrogothic and Byzantine Italy.</span>
Crude divorce rate is the ratio of the number of divorces to the average population in a given year. Divorce-marriage ratio is the ratio of the number of divorces to the number of marriages in a given year. Refined divorce rate is the ratio of divorces to the number of married women. Divorce rate is the general term for all of these ratios.
Thus, from the description, the answer is divorce-marriage ratio.
What structures are you talking about?
Answer:
Protocol.
Explanation:
As the exercise details, a protocol is a set of rules that determine what a layer would do and provides a clearly defined set of messages that software at the layer needs to understand. The word itself is related to a system of rules and acceptable behaviour. Therefore, the meaning of it in a corpus of programing is understandable.