Problem: The design architecture of USB is asymmetrical in its topology, consisting of a host, a multitude of downstream USB ports, and multiple peripheral devices connected in a tiered-star topology. Additional USB hubs may be included in the tiers, allowing branching into a tree structure with up to five tier levels. A USB host may implement multiple host controllers and each host controller may provide one or more USB ports. Up to 127 devices, including hub devices if present, may be connected to a single host controller. USB devices are linked in series through hubs. One hubbuilt into the host controlleris the root hub.
How are USB devices linked?
The answer is the following: in series through hubs

Problem: Except for a few primitive organisms such as sponges (which have no nervous system) and cnidarians (which have a nervous system consisting of a diffuse nerve net), all living multicellular animals are bilaterians, meaning animals with a bilaterally symmetric body shape (that is, left and right sides that are approximate mirror images of each other). All bilaterians are thought to have descended from a common ancestor that appeared early in the Cambrian period, 485-540 million years ago, and it has been hypothesized that this common ancestor had the shape of a simple tubeworm with a segmented body. At a schematic level, that basic worm-shape continues to be reflected in the body and nervous system architecture of all modern bilaterians, including vertebrates. The fundamental bilateral body form is a tube with a hollow gut cavity running from the mouth to the anus, and a nerve cord with an enlargement (a ganglion) for each body segment, with an especially large ganglion at the front, called the brain. The brain is small and simple in some species, such as nematode worms; in other species, including vertebrates, it is the most complex organ in the body. Some types of worms, such as leeches, also have an enlarged ganglion at the back end of the nerve cord, known as a "tail brain".
What type of creature has a ganglion at the back end of the nerve cord as well?
The answer is the following: leeches

Problem: Paris is a major rail, highway, and air transport hub. The Syndicat des transports d'Ile-de-France (STIF), formerly Syndicat des transports parisiens (STP), oversees the transit network in the region. The syndicate coordinates public transport and contracts it out to the RATP (operating 347 bus lines, the Metro, eight tramway lines, and sections of the RER), the SNCF (operating suburban rails, one tramway line and the other sections of the RER) and the Optile consortium of private operators managing 1,176 bus lines.
What was the STIF formerly known as?
The answer is the following: Syndicat des transports parisiens

Problem: The Umayyad Caliphate (Arabic: , trans. Al-Khilafat al-umawiyya) was the second of the four major Islamic caliphates established after the death of Muhammad. This caliphate was centered on the Umayyad dynasty (Arabic: , al-Umawiyyun, or , Banu Umayya, "Sons of Umayya"), hailing from Mecca. The Umayyad family had first come to power under the third caliph, Uthman ibn Affan (r. 644656), but the Umayyad regime was founded by Muawiya ibn Abi Sufyan, long-time governor of Syria, after the end of the First Muslim Civil War in 661 CE/41 AH. Syria remained the Umayyads' main power base thereafter, and Damascus was their capital. The Umayyads continued the Muslim conquests, incorporating the Caucasus, Transoxiana, Sindh, the Maghreb and the Iberian Peninsula (Al-Andalus) into the Muslim world. At its greatest extent, the Umayyad Caliphate covered 15 million km2 (5.79 million square miles), making it the largest empire (in terms of area - not in terms of population) the world had yet seen, and the fifth largest ever to exist.
How many million square miles was the Umayyad caliphate at its largest size?
The answer is the following:
5.79