Problem: Antibacterial antibiotics are commonly classified based on their mechanism of action, chemical structure, or spectrum of activity. Most target bacterial functions or growth processes. Those that target the bacterial cell wall (penicillins and cephalosporins) or the cell membrane (polymyxins), or interfere with essential bacterial enzymes (rifamycins, lipiarmycins, quinolones, and sulfonamides) have bactericidal activities. Those that target protein synthesis (macrolides, lincosamides and tetracyclines) are usually bacteriostatic (with the exception of bactericidal aminoglycosides). Further categorization is based on their target specificity. "Narrow-spectrum" antibacterial antibiotics target specific types of bacteria, such as Gram-negative or Gram-positive bacteria, whereas broad-spectrum antibiotics affect a wide range of bacteria. Following a 40-year hiatus in discovering new classes of antibacterial compounds, four new classes of antibacterial antibiotics have been brought into clinical use in the late 2000s and early 2010s: cyclic lipopeptides (such as daptomycin), glycylcyclines (such as tigecycline), oxazolidinones (such as linezolid), and lipiarmycins (such as fidaxomicin).
How many new classes of glycylcyclines was introduced in the late 2000's?
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Answer: unanswerable

Problem: Other less likely contenders are Guam and the United States Virgin Islands, both of which are unincorporated organized territories of the United States. Also, the Northern Mariana Islands and American Samoa, an unorganized, unincorporated territory, could both attempt to gain statehood. Some proposals call for the Virgin Islands to be admitted with Puerto Rico as one state (often known as the proposed "Commonwealth of Prusvi", for Puerto Rico/U.S. Virgin Islands, or as "Puerto Virgo"), and for the amalgamation of U.S. territories or former territories in the Pacific Ocean, in the manner of the "Greater Hawaii" concept of the 1960s. Guam and the Northern Mariana Islands would be admitted as one state, along with Palau, the Federated States of Micronesia, and the Marshall Islands (although these latter three entities are now separate sovereign nations, which have Compact of Free Association relationships with the United States). Such a state would have a population of 412,381 (slightly lower than Wyoming's population) and a land area of 911.82 square miles (2,361.6 km2) (slightly smaller than Rhode Island). American Samoa could possibly be part of such a state, increasing the population to 467,900 and the area to 988.65 square miles (2,560.6 km2). Radio Australia, in late May 2008, issued signs of Guam and the Northern Mariana Islands becoming one again and becoming the 51st state.
What entity reported on Guam and the Northern Mariana Islands becoming one again?
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Answer: Radio Australia

Problem: In July 2007, American business magnate and investor Warren Buffett's holding company Berkshire Hathaway bought an Israeli company, Iscar, its first non-U.S. acquisition, for $4 billion. Since the 1970s, Israel has received military aid from the United States, as well as economic assistance in the form of loan guarantees, which now account for roughly half of Israel's external debt. Israel has one of the lowest external debts in the developed world, and is a net lender in terms of net external debt (the total value of assets vs. liabilities in debt instruments owed abroad), which in December 2015[update] stood at a surplus of US$118 billion.
When did United States begin to provide foreign aid to Israel?
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Answer:
1970s