Problem: Predation:

Classification of predators by the extent to which they feed on and interact with their prey is one way ecologists may wish to categorize the different types of predation. Instead of focusing on what they eat, this system classifies predators by the way in which they eat, and the general nature of the interaction between predator and prey species. Two factors are considered here: How close the predator and prey are (in the latter two cases the term prey may be replaced with host) and whether or not the prey are directly murdered by the predator is considered, with true predation and parasitoidism involving certain death.

How many factors are used when studying how prey avoids their predator?
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A: unanswerable


Problem: Umayyad Caliphate:

The Diwan of Umar, assigning annuities to all Arabs and to the Muslim soldiers of other races, underwent a change in the hands of the Umayyads. The Umayyads meddled with the register and the recipients regarded pensions as the subsistence allowance even without being in active service. Hisham reformed it and paid only to those who participated in battle. On the pattern of the Byzantine system the Umayyads reformed their army organization in general and divided it into five corps: the centre, two wings, vanguards and rearguards, following the same formation while on march or on a battle field. Marwan II (740–50) abandoned the old division and introduced Kurdus (cohort), a small compact body. The Umayyad troops were divided into three divisions: infantry, cavalry and artillery. Arab troops were dressed and armed in Greek fashion. The Umayyad cavalry used plain and round saddles. The artillery used arradah (ballista), manjaniq (the mangonel) and dabbabah or kabsh (the battering ram). The heavy engines, siege machines and baggage were carried on camels behind the army.

What caliph reigned from 740 to 750?
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A: Marwan II


Problem: List of numbered streets in Manhattan:

The 132nd Street Community Garden is located on 132nd Street between Adam Clayton Powell Jr. Boulevard and Malcolm X Boulevard. In 1997, the lot received a garden makeover; the Borough President's office funded the installation of a $100,000 water distribution system that keeps the wide variety of trees green. The garden also holds a goldfish pond and several benches. The spirit of the neighborhood lives in gardens like this one, planted and tended by local residents.

Who funded the 132nd Street Community Garden's water distribution system?
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A: Borough President's office


Problem: Separation of powers under the United States Constitution:

Some of Jackson's successors made no use of the veto power, while others used it intermittently. It was only after the Civil War that presidents began to use the power to truly counterbalance Congress. Andrew Johnson, a Democrat, vetoed several Reconstruction bills passed by the "Radical Republicans." Congress, however, managed to override fifteen of Johnson's twenty-nine vetoes. Furthermore, it attempted to curb the power of the presidency by passing the Tenure of Office Act. The Act required Senate approval for the dismissal of senior Cabinet officials. When Johnson deliberately violated the Act, which he felt was unconstitutional (Supreme Court decisions later vindicated such a position), the House of Representatives impeached him; he was acquitted in the Senate by one vote.

After which war did Congress begin using power to counterbalance the President?
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A:
unanswerable