QUES: In the US Air Force, the distinction between bombers, fighters that are actually fighter-bombers, and attack aircraft has become blurred. Many attack aircraft, even ones that look like fighters, are optimized to drop bombs, with very little ability to engage in aerial combat. Many fighter aircraft, such as the F-16, are often used as 'bomb trucks', despite being designed for aerial combat. Perhaps the one meaningful distinction at present is the question of range: a bomber is generally a long-range aircraft capable of striking targets deep within enemy territory, whereas fighter bombers and attack aircraft are limited to 'theater' missions in and around the immediate area of battlefield combat. Even that distinction is muddied by the availability of aerial refueling, which greatly increases the potential radius of combat operations. The US, Russia, and the People's Republic of China operate strategic bombers.
What increases the radius of combat missions by the US Air Force?

ANS: aerial refueling

QUES: Marvel earned a great deal of money and recognition during the comic book boom of the early 1990s, launching the successful 2099 line of comics set in the future (Spider-Man 2099, etc.) and the creatively daring though commercially unsuccessful Razorline imprint of superhero comics created by novelist and filmmaker Clive Barker. In 1990, Marvel began selling Marvel Universe Cards with trading card maker SkyBox International. These were collectible trading cards that featured the characters and events of the Marvel Universe. The 1990s saw the rise of variant covers, cover enhancements, swimsuit issues, and company-wide crossovers that affected the overall continuity of the fictional Marvel Universe
When did comic book sales begin to decline?

ANS: unanswerable

QUES: During the Cambrian period, Gondwana had a mild climate. West Antarctica was partially in the Northern Hemisphere, and during this period large amounts of sandstones, limestones and shales were deposited. East Antarctica was at the equator, where sea floor invertebrates and trilobites flourished in the tropical seas. By the start of the Devonian period (416 Ma), Gondwana was in more southern latitudes and the climate was cooler, though fossils of land plants are known from this time. Sand and silts were laid down in what is now the Ellsworth, Horlick and Pensacola Mountains. Glaciation began at the end of the Devonian period (360 Ma), as Gondwana became centered on the South Pole and the climate cooled, though flora remained. During the Permian period, the land became dominated by seed plants such as Glossopteris, a pteridosperm which grew in swamps. Over time these swamps became deposits of coal in the Transantarctic Mountains. Towards the end of the Permian period, continued warming led to a dry, hot climate over much of Gondwana.
What type of climate did Gondwana have during the Cambrian period?

ANS: mild

QUES: Gray does not, however, give any indication of what available evidence these theories were at odds with, and his appeal to "crucial support" illustrates the very inductivist approach to science that Popper sought to show was logically illegitimate. For, according to Popper, Einstein's theory was at least equally as well corroborated as Newton's upon its initial conception; they both equally well accounted for all the hitherto available evidence. Moreover, since Einstein also explained the empirical refutations of Newton's theory, general relativity was immediately deemed suitable for tentative acceptance on the Popperian account. Indeed, Popper wrote, several decades before Gray's criticism, in reply to a critical essay by Imre Lakatos:
Who wrote several decades after Gray's criticism?

ANS:
unanswerable