Question: The city shares a 15-mile (24 km) border with Mexico that includes two border crossings. San Diego hosts the busiest international border crossing in the world, in the San Ysidro neighborhood at the San Ysidro Port of Entry. A second, primarily commercial border crossing operates in the Otay Mesa area; it is the largest commercial crossing on the California-Baja California border and handles the third-highest volume of trucks and dollar value of trade among all United States-Mexico land crossings.
Is there an answer to this question: How many border crossings does San Francisco share with Mexico?

Answer: unanswerable

Question: In the years to follow, public revelations on the state of Charles and Diana's marriage continued. Even though support for republicanism in Britain seemed higher than at any time in living memory, republicanism was still a minority viewpoint, and the Queen herself had high approval ratings. Criticism was focused on the institution of the monarchy itself and the Queen's wider family rather than her own behaviour and actions. In consultation with her husband and the Prime Minister, John Major, as well as the Archbishop of Canterbury, George Carey, and her private secretary, Robert Fellowes, she wrote to Charles and Diana at the end of December 1995, saying that a divorce was desirable.
Is there an answer to this question: In spite of criticisms what kind of approval ratings did Elizabeth have?

Answer: high

Question: Railways must operate at variable speeds. Until the mid 1980s this was only practical with the brush-type DC motor, although such DC can be supplied from an AC catenary via on-board electric power conversion. Since such conversion was not well developed in the late 19th century and early 20th century, most early electrified railways used DC and many still do, particularly rapid transit (subways) and trams. Speed was controlled by connecting the traction motors in various series-parallel combinations, by varying the traction motors' fields, and by inserting and removing starting resistances to limit motor current.
Is there an answer to this question: What must operate at constant speeds?

Answer: unanswerable

Question: This work has been pioneered by John B. Cobb, Jr., whose book Is It Too Late? A Theology of Ecology (1971) was the first single-authored book in environmental ethics. Cobb also co-authored a book with economist Herman Daly entitled For the Common Good: Redirecting the Economy toward Community, the Environment, and a Sustainable Future (1989), which applied Whitehead's thought to economics, and received the Grawemeyer Award for Ideas Improving World Order. Cobb followed this with a second book, Sustaining the Common Good: A Christian Perspective on the Global Economy (1994), which aimed to challenge "economists' zealous faith in the great god of growth."
Is there an answer to this question: What was the goal of Cobb's second book on economics?

Answer:
to challenge "economists' zealous faith in the great god of growth."