QUES: It is estimated that in 480 BC, 50 million people lived in the Achaemenid Empire. The empire at its peak ruled over 44% of the world's population, the highest such figure for any empire in history. In Greek history, the Achaemenid Empire is considered as the antagonist of the Greek city states, for the emancipation of slaves including the Jewish exiles in Babylon, building infrastructures such as road and postal systems, and the use of an official language, the Imperial Aramaic, throughout its territories. The empire had a centralized, bureaucratic administration under the emperor, a large professional army, and civil services, inspiring similar developments in later empires. Furthermore, one of the Seven Wonders of the Ancient World, the Mausoleum at Halicarnassus, was built in the empire between 353 and 350 BC.
What Seven Wonder of the Ancient world was built by the Archaemenid Empire in the 4th Century BC?

ANS: the Mausoleum at Halicarnassus

QUES: Copper, silver and gold are in group 11 of the periodic table, and they share certain attributes: they have one s-orbital electron on top of a filled d-electron shell and are characterized by high ductility and electrical conductivity. The filled d-shells in these elements do not contribute much to the interatomic interactions, which are dominated by the s-electrons through metallic bonds. Unlike metals with incomplete d-shells, metallic bonds in copper are lacking a covalent character and are relatively weak. This explains the low hardness and high ductility of single crystals of copper. At the macroscopic scale, introduction of extended defects to the crystal lattice, such as grain boundaries, hinders flow of the material under applied stress, thereby increasing its hardness. For this reason, copper is usually supplied in a fine-grained polycrystalline form, which has greater strength than monocrystalline forms.
What is copper normally missing?

ANS: unanswerable

QUES: The idea of building a tunnel under the Irish Sea has been raised since 1895, when it was first investigated. Several potential Irish Sea tunnel projects have been proposed, most recently the Tusker Tunnel between the ports of Rosslare and Fishguard proposed by The Institute of Engineers of Ireland in 2004. A rail tunnel was proposed in 1997 on a different route, between Dublin and Holyhead, by British engineering firm Symonds. Either tunnel, at 50 mi (80 km), would be by far the longest in the world, and would cost an estimated 15 billion or 20 billion. A proposal in 2007, estimated the cost of building a bridge from County Antrim in Northern Ireland to Galloway in Scotland at 3.5bn (5bn).
Who proposed the Tusker Tunnel?

ANS: The Institute of Engineers of Ireland

QUES: A commandery consisted of a group of counties, and was headed by an Administrator. He was the top civil and military leader of the commandery and handled defense, lawsuits, seasonal instructions to farmers and recommendations of nominees for office sent annually to the capital in a quota system first established by Emperor Wu. The head of a large county of about 10,000 households was called a Prefect, while the heads of smaller counties were called Chiefs, and both could be referred to as Magistrates. A Magistrate maintained law and order in his county, registered the populace for taxation, mobilized commoners for annual corvee duties, repaired schools and supervised public works.
Around how many households was a Prefect responsible for?

ANS:
10,000