QUES: The opening years of the 1980s saw a number of changes in personnel and direction of established hard rock acts, including the deaths of Bon Scott, the lead singer of AC/DC, and John Bonham, drummer with Led Zeppelin. Whereas Zeppelin broke up almost immediately afterwards, AC/DC pressed on, recording the album Back in Black (1980) with their new lead singer, Brian Johnson. It became the fifth-highest-selling album of all time in the US and the second-highest-selling album in the world. Black Sabbath had split with original singer Ozzy Osbourne in 1979 and replaced him with Ronnie James Dio, formerly of Rainbow, giving the band a new sound and a period of creativity and popularity beginning with Heaven and Hell (1980). Osbourne embarked on a solo career with Blizzard of Ozz (1980), featuring American guitarist Randy Rhoads. Some bands, such as Queen, moved away from their hard rock roots and more towards pop rock, while others, including Rush with Moving Pictures (1981), began to return to a hard rock sound. The creation of thrash metal, which mixed heavy metal with elements of hardcore punk from about 1982, particularly by Metallica, Anthrax, Megadeth and Slayer, helped to create extreme metal and further remove the style from hard rock, although a number of these bands or their members would continue to record some songs closer to a hard rock sound. Kiss moved away from their hard rock roots toward pop metal: firstly removing their makeup in 1983 for their Lick It Up album, and then adopting the visual and sound of glam metal for their 1984 release, Animalize, both of which marked a return to commercial success. Pat Benatar was one of the first women to achieve commercial success in hard rock, with three successive Top 5 albums between 1980 and 1982.
When was Bon Scott born?

ANS: unanswerable

QUES: In the late 14th century, the Songhai gradually gained independence from the Mali Empire and expanded, ultimately subsuming the entire eastern portion of the Mali Empire. The Songhai Empire's eventual collapse was largely the result of a Moroccan invasion in 1591, under the command of Judar Pasha. The fall of the Songhai Empire marked the end of the region's role as a trading crossroads. Following the establishment of sea routes by the European powers, the trans-Saharan trade routes lost significance.
Who was the commander of the Moroccan invasion of 1591?

ANS: Judar Pasha

QUES: The Glastonbury Festival of Contemporary Performing Arts takes place most years in Pilton, near Shepton Mallet, attracting over 170,000 music and culture lovers from around the world to see world-famous entertainers. The Big Green Gathering which grew out of the Green fields at the Glastonbury Festival is held in the Mendip Hills between Charterhouse and Compton Martin each summer. The annual Bath Literature Festival is one of several local festivals in the county; others include the Frome Festival and the Trowbridge Village Pump Festival, which, despite its name, is held at Farleigh Hungerford in Somerset. The annual circuit of West Country Carnivals is held in a variety of Somerset towns during the autumn, forming a major regional festival, and the largest Festival of Lights in Europe.
The annual Carnival is held when and where

ANS: The annual circuit of West Country Carnivals is held in a variety of Somerset towns during the autumn

QUES: Von Neumann made fundamental contributions to mathematical statistics. In 1941, he derived the exact distribution of the ratio of the mean square of successive differences to the sample variance for independent and identically normally distributed variables. This ratio was applied to the residuals from regression models and is commonly known as the DurbinWatson statistic for testing the null hypothesis that the errors are serially independent against the alternative that they follow a stationary first order autoregression.
How has mean square ratio been applied?

ANS:
DurbinWatson statistic