Problem: IPod:

The iPod has also been credited with accelerating shifts within the music industry. The iPod's popularization of digital music storage allows users to abandon listening to entire albums and instead be able to choose specific singles which hastened the end of the Album Era in popular music.

The ease of collecting singles with the iPod and iTunes is credited with ending what "era" in pop music?
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A: the Album Era

Problem: Indigenous peoples of the Americas:

The European colonization of the Americas forever changed the lives and cultures of the peoples of the continents. Although the exact pre-contact population of the Americas is unknown, scholars estimate that Native American populations diminished by between 80 and 90% within the first centuries of contact with Europeans. The leading cause was disease. The continent was ravaged by epidemics of diseases such as smallpox, measles, and cholera, which were brought from Europe by the early explorers and spread quickly into new areas even before later explorers and colonists reached them. Native Americans suffered high mortality rates due to their lack of prior exposure to these diseases. The loss of lives was exacerbated by conflict between colonists and indigenous people. Colonists also frequently perpetrated massacres on the indigenous groups and enslaved them. According to the U.S. Bureau of the Census (1894), the North American Indian Wars of the 19th century cost the lives of about 19,000 whites and 30,000 Native Americans.

Why did Native Americans suffer such high mortality rates to the diseases?
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A: lack of prior exposure

Problem: Cardinal (Catholicism):

There are seven suburbicarian sees: Ostia, Albano, Porto and Santa Rufina, Palestrina, Sabina and Mentana, Frascati and Velletri. Velletri was united with Ostia from 1150 until 1914, when Pope Pius X separated them again, but decreed that whatever cardinal bishop became Dean of the College of Cardinals would keep the suburbicarian see he already held, adding to it that of Ostia, with the result that there continued to be only six cardinal bishops.

What are the name of the eight suburbicarian sees?
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A: unanswerable

Problem: Immunology:

Clinical immunology is the study of diseases caused by disorders of the immune system (failure, aberrant action, and malignant growth of the cellular elements of the system). It also involves diseases of other systems, where immune reactions play a part in the pathology and clinical features.

The study of diseases caused by immune system disorders is called?
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A:
Clinical immunology