Problem: During adolescence, the human body undergoes various physical, physiological and immunological changes triggered and mediated by hormones, of which the most significant in females is 17-β-oestradiol (an oestrogen) and, in males, is testosterone. Oestradiol usually begins to act around the age of 10 and testosterone some months later. There is evidence that these steroids act directly not only on the primary and secondary sexual characteristics but also have an effect on the development and regulation of the immune system, including an increased risk in developing pubescent and post-pubescent autoimmunity. There is also some evidence that cell surface receptors on B cells and macrophages may detect sex hormones in the system.
Evidence suggests that receptors on B cells may do what?
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Answer: detect sex hormones in the system


Problem: The coastal plain transitions to the Piedmont region along the Atlantic Seaboard fall line, a line which marks the elevation at which waterfalls first appear on streams and rivers. The Piedmont region of central North Carolina is the state's most urbanized and densely populated section. It consists of gently rolling countryside frequently broken by hills or low mountain ridges. Small, isolated, and deeply eroded mountain ranges and peaks are located in the Piedmont, including the Sauratown Mountains, Pilot Mountain, the Uwharrie Mountains, Crowder's Mountain, King's Pinnacle, the Brushy Mountains, and the South Mountains. The Piedmont ranges from about 300 to 400 feet (91 to 122 m) in elevation in the east to over 1,000 feet (300 m) in the west. Because of the rapid population growth in the Piedmont, a significant part of the rural area in this region is being transformed into suburbs with shopping centers, housing, and corporate offices. Agriculture is steadily declining in importance. The major rivers of the Piedmont, such as the Yadkin and Catawba, tend to be fast-flowing, shallow, and narrow.
Pilot Mountain and South Mountains are located in what region of North Carolina?
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Answer: Piedmont


Problem: Liberia scored a 3.3 on a scale from 10 (highly clean) to 0 (highly corrupt) on the 2010 Corruption Perceptions Index. This gave it a ranking 87th of 178 countries worldwide and 11th of 47 in Sub-Saharan Africa. This score represented a significant improvement since 2007, when the country scored 2.1 and ranked 150th of 180 countries. When seeking attention of a selection of service[clarification needed] providers, 89% of Liberians had to pay a bribe, the highest national percentage in the world according to the organization's 2010 Global Corruption Barometer.
What was Liberia's ranking compared to the other 176 countries?
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Answer:
87th