Problem: Police:

Modern police forces make extensive use of radio communications equipment, carried both on the person and installed in vehicles, to co-ordinate their work, share information, and get help quickly. In recent years, vehicle-installed computers have enhanced the ability of police communications, enabling easier dispatching of calls, criminal background checks on persons of interest to be completed in a matter of seconds, and updating officers' daily activity log and other, required reports on a real-time basis. Other common pieces of police equipment include flashlights/torches, whistles, police notebooks and "ticket books" or citations.

Why don't police use radios?
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A: unanswerable


Problem: Alfred North Whitehead:

The two volume biography of Whitehead by Victor Lowe is the most definitive presentation of the life of Whitehead. However, many details of Whitehead's life remain obscure because he left no Nachlass; his family carried out his instructions that all of his papers be destroyed after his death. Additionally, Whitehead was known for his "almost fanatical belief in the right to privacy", and for writing very few personal letters of the kind that would help to gain insight on his life. This led to Lowe himself remarking on the first page of Whitehead's biography, "No professional biographer in his right mind would touch him."

 Why was every Nachlass left behind after Whitehead's death?
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A: unanswerable


Problem: Muslim world:

The Solar Hijri calendar, also called the Shamsi Hijri calendar, and abbreviated as SH, is the official calendar of Iran and Afghanistan. It begins on the vernal equinox. Each of the twelve months corresponds with a zodiac sign. The first six months have 31 days, the next five have 30 days, and the last month has 29 days in usual years but 30 days in leap years. The year of Prophet Muhammad's migration to Medina (622 CE) is fixed as the first year of the calendar, and the New Year's Day always falls on the March equinox.

What is the customary calendar of Iran?
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A: the Shamsi Hijri calendar


Problem: Materialism:

In Ancient Indian philosophy, materialism developed around 600 BC with the works of Ajita Kesakambali, Payasi, Kanada, and the proponents of the Cārvāka school of philosophy. Kanada became one of the early proponents of atomism. The Nyaya–Vaisesika school (600 BC - 100 BC) developed one of the earliest forms of atomism, though their proofs of God and their positing that the consciousness was not material precludes labelling them as materialists. Buddhist atomism and the Jaina school continued the atomic tradition.

Around what time did materialism become part of Ancient Indian philosophy?
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A:
600 BC