Problem: Underpinning Houston's land surface are unconsolidated clays, clay shales, and poorly cemented sands up to several miles deep. The region's geology developed from river deposits formed from the erosion of the Rocky Mountains. These sediments consist of a series of sands and clays deposited on decaying organic marine matter, that over time, transformed into oil and natural gas. Beneath the layers of sediment is a water-deposited layer of halite, a rock salt. The porous layers were compressed over time and forced upward. As it pushed upward, the salt dragged surrounding sediments into salt dome formations, often trapping oil and gas that seeped from the surrounding porous sands. The thick, rich, sometimes black, surface soil is suitable for rice farming in suburban outskirts where the city continues to grow.
Besides sands, what are the foundations of Houston's land?
The answer is the following: clays

Problem: In 1978, Sewall Wright suggested that human populations that have long inhabited separated parts of the world should, in general, be considered different subspecies by the usual criterion that most individuals of such populations can be allocated correctly by inspection. Wright argued that it does not require a trained anthropologist to classify an array of Englishmen, West Africans, and Chinese with 100% accuracy by features, skin color, and type of hair despite so much variability within each of these groups that every individual can easily be distinguished from every other. However, it is customary to use the term race rather than subspecies for the major subdivisions of the human species as well as for minor ones.
How should populations long inhabiting separate parts of the world be considered?
The answer is the following: different subspecies

Problem: As of 2013, the global advertising agencies of Omnicom Group and Interpublic Group, both based in Manhattan, had combined annual revenues of approximately US$21 billion, reflecting New York City's role as the top global center for the advertising industry, which is metonymously referred to as "Madison Avenue". The city's fashion industry provides approximately 180,000 employees with $11 billion in annual wages.
About how many people work in the New York fashion industry?
The answer is the following: 180,000

Problem: The meaning and origin of many archaic festivals baffled even Rome's intellectual elite, but the more obscure they were, the greater the opportunity for reinvention and reinterpretation — a fact lost neither on Augustus in his program of religious reform, which often cloaked autocratic innovation, nor on his only rival as mythmaker of the era, Ovid. In his Fasti, a long-form poem covering Roman holidays from January to June, Ovid presents a unique look at Roman antiquarian lore, popular customs, and religious practice that is by turns imaginative, entertaining, high-minded, and scurrilous; not a priestly account, despite the speaker's pose as a vates or inspired poet-prophet, but a work of description, imagination and poetic etymology that reflects the broad humor and burlesque spirit of such venerable festivals as the Saturnalia, Consualia, and feast of Anna Perenna on the Ides of March, where Ovid treats the assassination of the newly deified Julius Caesar as utterly incidental to the festivities among the Roman people. But official calendars preserved from different times and places also show a flexibility in omitting or expanding events, indicating that there was no single static and authoritative calendar of required observances. In the later Empire under Christian rule, the new Christian festivals were incorporated into the existing framework of the Roman calendar, alongside at least some of the traditional festivals.
What did obscure festivals offer Romans the opportunity to do?
The answer is the following:
reinterpretation