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While these few hard rock bands managed to maintain success and popularity in the early part of the decade, alternative forms of hard rock achieved mainstream success in the form of grunge in the US and Britpop in the UK. This was particularly evident after the success of Nirvana's Nevermind (1991), which combined elements of hardcore punk and heavy metal into a "dirty" sound that made use of heavy guitar distortion, fuzz and feedback, along with darker lyrical themes than their "hair band" predecessors. Although most grunge bands had a sound that sharply contrasted mainstream hard rock, several, including Pearl Jam, Alice in Chains, Mother Love Bone and Soundgarden, were more strongly influenced by 1970s and 1980s rock and metal, while Stone Temple Pilots managed to turn alternative rock into a form of stadium rock. However, all grunge bands shunned the macho, anthemic and fashion-focused aesthetics particularly associated with glam metal. In the UK, Oasis were unusual among the Britpop bands of the mid-1990s in incorporating a hard rock sound.

What was the hard rock style that emerged in the early 1990s?
Answer: grunge
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New Yorkoften called New York City or the City of New York to distinguish it from the State of New York, of which it is a partis the most populous city in the United States and the center of the New York metropolitan area, the premier gateway for legal immigration to the United States and one of the most populous urban agglomerations in the world. A global power city, New York exerts a significant impact upon commerce, finance, media, art, fashion, research, technology, education, and entertainment, its fast pace defining the term New York minute. Home to the headquarters of the United Nations, New York is an important center for international diplomacy and has been described as the cultural and financial capital of the world.

What city in the United States has the highest population?
Answer: New York
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The phase of reflection of electromagnetic waves depends on the polarization of the incident wave. Given the larger refractive index of the ground (typically n=2) compared to air (n=1), the phase of horizontally polarized radiation is reversed upon reflection (a phase shift of radians or 180). On the other hand, the vertical component of the wave's electric field is reflected at grazing angles of incidence approximately in phase. These phase shifts apply as well to a ground modelled as a good electrical conductor.

What is the refractive index of air?
Answer:
n=1