In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

Tibet's incursions into Sichuan can be classified as what during the Tang Dynasty?, Context: Sichuan came under the firm control of a Chinese central government during the Sui dynasty, but it was during the subsequent Tang dynasty where Sichuan regained its previous political and cultural prominence for which it was known during the Han. Chengdu became nationally known as a supplier of armies and the home of Du Fu, who is sometimes called China's greatest poet. During the An Lushan Rebellion (755-763), Emperor Xuanzong of Tang fled from Chang'an to Sichuan. The region was torn by constant warfare and economic distress as it was besieged by the Tibetan Empire.
constant

What else should be watched for?, Context: Shortness of breath occurs when the damage to the heart limits the output of the left ventricle, causing left ventricular failure and consequent pulmonary edema. Other symptoms include diaphoresis (an excessive form of sweating), weakness, light-headedness, nausea, vomiting, and palpitations. These symptoms are likely induced by a massive surge of catecholamines from the sympathetic nervous system, which occurs in response to pain and the blood flow abnormalities that result from dysfunction of the heart muscle. Loss of consciousness (due to inadequate blood flow to the brain and cardiogenic shock) and sudden death (frequently due to the development of ventricular fibrillation) can occur in MIs.
Other symptoms include diaphoresis (an excessive form of sweating), weakness, light-headedness, nausea, vomiting, and palpitations

Who listed the amount of manpower available to Rome via their own forces as well as those of their allies?, Context: Rome's military confederation with the other peoples of the Italian peninsula meant that half of Rome's army was provided by the Socii, such as the Etruscans, Umbrians, Apulians, Campanians, Samnites, Lucani, Bruttii, and the various southern Greek cities. Polybius states that Rome could draw on 770,000 men at the beginning of the Second Punic War, of which 700,000 were infantry and 70,000 met the requirements for cavalry. Rome's Italian allies would be organized in alae, or wings, roughly equal in manpower to the Roman legions, though with 900 cavalry instead of 300.
Polybius