Problem: Macintosh:

Originally, the hardware architecture was so closely tied to the Mac OS operating system that it was impossible to boot an alternative operating system. The most common workaround, is to boot into Mac OS and then to hand over control to a Mac OS-based bootloader application. Used even by Apple for A/UX and MkLinux, this technique is no longer necessary since the introduction of Open Firmware-based PCI Macs, though it was formerly used for convenience on many Old World ROM systems due to bugs in the firmware implementation.[citation needed] Now, Mac hardware boots directly from Open Firmware in most PowerPC-based Macs or EFI in all Intel-based Macs.

Where does Mac hardware boot indirectly to in all Intel-based Macs?
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A: unanswerable


Problem: Korean War:

While these preparations were underway in the North, there were frequent clashes along the 38th parallel, especially at Kaesong and Ongjin, many initiated by the South. The Republic of Korea Army (ROK Army) was being trained by the U.S. Korean Military Advisory Group (KMAG). On the eve of war, KMAG's commander General William Lynn Roberts voiced utmost confidence in the ROK Army and boasted that any North Korean invasion would merely provide "target practice". For his part, Syngman Rhee repeatedly expressed his desire to conquer the North, including when American diplomat John Foster Dulles visited Korea on 18 June.

Who was the diplomat that visited Korea?
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A: John Foster Dulles


Problem: Armenia:

A wide array of sports are played in Armenia, the most popular among them being wrestling, weightlifting, judo, association football, chess, and boxing. Armenia's mountainous terrain provides great opportunities for the practice of sports like skiing and climbing. Being a landlocked country, water sports can only be practiced on lakes, notably Lake Sevan. Competitively, Armenia has been successful in chess, weightlifting and wrestling at the international level. Armenia is also an active member of the international sports community, with full membership in the Union of European Football Associations (UEFA) and International Ice Hockey Federation (IIHF). It also hosts the Pan-Armenian Games.

What international sports has Armenia done well at?
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A: chess, weightlifting and wrestling


Problem: Copper:

There are 29 isotopes of copper. 63Cu and 65Cu are stable, with 63Cu comprising approximately 69% of naturally occurring copper; they both have a spin of 3⁄2. The other isotopes are radioactive, with the most stable being 67Cu with a half-life of 61.83 hours. Seven metastable isotopes have been characterized, with 68mCu the longest-lived with a half-life of 3.8 minutes. Isotopes with a mass number above 64 decay by β−, whereas those with a mass number below 64 decay by β+. 64Cu, which has a half-life of 12.7 hours, decays both ways.

Which isotope makes up about 69% of natural copper?
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A:
63Cu