Problem: Disease can arise if the host's protective immune mechanisms are compromised and the organism inflicts damage on the host. Microorganisms can cause tissue damage by releasing a variety of toxins or destructive enzymes. For example, Clostridium tetani releases a toxin that paralyzes muscles, and staphylococcus releases toxins that produce shock and sepsis. Not all infectious agents cause disease in all hosts. For example, less than 5% of individuals infected with polio develop disease. On the other hand, some infectious agents are highly virulent. The prion causing mad cow disease and Creutzfeldt–Jakob disease invariably kills all animals and people that are infected.
What percentage of people infected with polio develop disease?
The answer is the following: less than 5%

Problem: At the end of the first decade of the 21st century, downtown Tucson underwent a revitalization effort by city planners and the business community. The primary project was Rio Nuevo, a large retail and community center that has been stalled in planning for more than ten years. Downtown is generally regarded as the area bordered by 17th Street to the south, I-10 to the west, and 6th Street to the north, and Toole Avenue and the Union Pacific (formerly Southern Pacific) railroad tracks, site of the historic train depot and "Locomotive #1673", built in 1900. Downtown is divided into the Presidio District, the Barrio Viejo, and the Congress Street Arts and Entertainment District. Some authorities include the 4th Avenue shopping district, which is set just northeast of the rest of downtown and connected by an underpass beneath the UPRR tracks.
What is the western edge of Tucson's downtown?
The answer is the following: I-10

Problem: In the Middle Ages, the Church and the worldly authorities were closely related. Martin Luther separated the religious and the worldly realms in principle (doctrine of the two kingdoms). The believers were obliged to use reason to govern the worldly sphere in an orderly and peaceful way. Luther's doctrine of the priesthood of all believers upgraded the role of laymen in the church considerably. The members of a congregation had the right to elect a minister and, if necessary, to vote for his dismissal (Treatise On the right and authority of a Christian assembly or congregation to judge all doctrines and to call, install and dismiss teachers, as testified in Scripture; 1523). Calvin strengthened this basically democratic approach by including elected laymen (church elders, presbyters) in his representative church government. The Huguenots added regional synods and a national synod, whose members were elected by the congregations, to Calvin's system of church self-government. This system was taken over by the other reformed churches.
Who added synods to church government?
The answer is the following: The Huguenots

Problem: Carolingian art was produced for a small group of figures around the court, and the monasteries and churches they supported. It was dominated by efforts to regain the dignity and classicism of imperial Roman and Byzantine art, but was also influenced by the Insular art of the British Isles. Insular art integrated the energy of Irish Celtic and Anglo-Saxon Germanic styles of ornament with Mediterranean forms such as the book, and established many characteristics of art for the rest of the medieval period. Surviving religious works from the Early Middle Ages are mostly illuminated manuscripts and carved ivories, originally made for metalwork that has since been melted down. Objects in precious metals were the most prestigious form of art, but almost all are lost except for a few crosses such as the Cross of Lothair, several reliquaries, and finds such as the Anglo-Saxon burial at Sutton Hoo and the hoards of Gourdon from Merovingian France, Guarrazar from Visigothic Spain and Nagyszentmiklós near Byzantine territory. There are survivals from the large brooches in fibula or penannular form that were a key piece of personal adornment for elites, including the Irish Tara Brooch. Highly decorated books were mostly Gospel Books and these have survived in larger numbers, including the Insular Book of Kells, the Book of Lindisfarne, and the imperial Codex Aureus of St. Emmeram, which is one of the few to retain its "treasure binding" of gold encrusted with jewels. Charlemagne's court seems to have been responsible for the acceptance of figurative monumental sculpture in Christian art, and by the end of the period near life-sized figures such as the Gero Cross were common in important churches.
Along with carved ivories, what religious works of the Early Middle Ages were common?
The answer is the following:
illuminated manuscripts