Problem: Mammal:

Recent molecular phylogenetic studies suggest that most placental orders diverged about 100 to 85 million years ago and that modern families appeared in the period from the late Eocene through the Miocene. But paleontologists object that no placental fossils have been found from before the end of the Cretaceous. The earliest undisputed fossils of placentals come from the early Paleocene, after the extinction of the dinosaurs. In particular, scientists have recently identified an early Paleocene animal named Protungulatum donnae as one of the first placental mammals. The earliest known ancestor of primates is Archicebus achilles from around 55 million years ago. This tiny primate weighed 2030 grams (0.71.1 ounce) and could fit within a human palm.

What is the earliest ancestor of humans from about 55 million years ago?
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A: unanswerable

Problem: Washington University in St. Louis:

The Washington University School of Medicine, founded in 1891, is highly regarded as one of the world's leading centers for medical research and training. The School ranks first in the nation in student selectivity. Among its many recent initiatives, The Genome Center at Washington University (directed by Richard K. Wilson) played a leading role in the Human Genome Project, having contributed 25% of the finished sequence. The School pioneered bedside teaching and led in the transformation of empirical knowledge into scientific medicine. The medical school partners with St. Louis Children's Hospital and Barnes-Jewish Hospital (part of BJC HealthCare), where all physicians are members of the school's faculty.

Who directs the Washington University School of Medicine?
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A: unanswerable

Problem: Pain:

In 1644, Rene Descartes theorized that pain was a disturbance that passed down along nerve fibers until the disturbance reached the brain, a development that transformed the perception of pain from a spiritual, mystical experience to a physical, mechanical sensation[citation needed]. Descartes's work, along with Avicenna's, prefigured the 19th-century development of specificity theory. Specificity theory saw pain as "a specific sensation, with its own sensory apparatus independent of touch and other senses". Another theory that came to prominence in the 18th and 19th centuries was intensive theory, which conceived of pain not as a unique sensory modality, but an emotional state produced by stronger than normal stimuli such as intense light, pressure or temperature. By the mid-1890s, specificity was backed mostly by physiologists and physicians, and the intensive theory was mostly backed by psychologists. However, after a series of clinical observations by Henry Head and experiments by Max von Frey, the psychologists migrated to specificity almost en masse, and by century's end, most textbooks on physiology and psychology were presenting pain specificity as fact.

Who theorized about pain in 1464?
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A: unanswerable

Problem: Hard rock:

The roots of hard rock can be traced back to the 1950s, particularly electric blues, which laid the foundations for key elements such as a rough declamatory vocal style, heavy guitar riffs, string-bending blues-scale guitar solos, strong beat, thick riff-laden texture, and posturing performances. Electric blues guitarists began experimenting with hard rock elements such as driving rhythms, distorted guitar solos and power chords in the 1950s, evident in the work of Memphis blues guitarists such as Joe Hill Louis, Willie Johnson, and particularly Pat Hare, who captured a "grittier, nastier, more ferocious electric guitar sound" on records such as James Cotton's "Cotton Crop Blues" (1954). Other antecedents include Link Wray's instrumental "Rumble" in 1958, and the surf rock instrumentals of Dick Dale, such as "Let's Go Trippin'" (1961) and "Misirlou" (1962).

Who recorded "Rumble"?
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A:
Link Wray