Problem: Annelid:

The fluid in the coelomata contains coelomocyte cells that defend the animals against parasites and infections. In some species coelomocytes may also contain a respiratory pigment red hemoglobin in some species, green chlorocruorin in others (dissolved in the plasma) and provide oxygen transport within their segments. Respiratory pigment is also dissolved in the blood plasma. Species with well-developed septa generally also have blood vessels running all long their bodies above and below the gut, the upper one carrying blood forwards while the lower one carries it backwards. Networks of capillaries in the body wall and around the gut transfer blood between the main blood vessels and to parts of the segment that need oxygen and nutrients. Both of the major vessels, especially the upper one, can pump blood by contracting. In some annelids the forward end of the upper blood vessel is enlarged with muscles to form a heart, while in the forward ends of many earthworms some of the vessels that connect the upper and lower main vessels function as hearts. Species with poorly developed or no septa generally have no blood vessels and rely on the circulation within the coelom for delivering nutrients and oxygen.

What can coelomocyte cells heal?
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A: unanswerable

Problem: Time:

In non-relativistic classical mechanics, Newton's concept of "relative, apparent, and common time" can be used in the formulation of a prescription for the synchronization of clocks. Events seen by two different observers in motion relative to each other produce a mathematical concept of time that works sufficiently well for describing the everyday phenomena of most people's experience. In the late nineteenth century, physicists encountered problems with the classical understanding of time, in connection with the behavior of electricity and magnetism. Einstein resolved these problems by invoking a method of synchronizing clocks using the constant, finite speed of light as the maximum signal velocity. This led directly to the result that observers in motion relative to one another measure different elapsed times for the same event.

In which century did physicists encounter problems with the understanding of time?
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A: the late nineteenth century

Problem: Cyprus:

On 15 July 1974, the Greek military junta under Dimitrios Ioannides carried out a coup d'etat in Cyprus, to unite the island with Greece. The coup ousted president Makarios III and replaced him with pro-enosis nationalist Nikos Sampson. In response to the coup, five days later, on 20 July 1974, the Turkish army invaded the island, citing a right to intervene to restore the constitutional order from the 1960 Treaty of Guarantee. This justification has been rejected by the United Nations and the international community.

What date was a coup d'etat carried out in Cyprus?
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A: 15 July 1974

Problem: Computer:

The tide-predicting machine invented by Sir William Thomson in 1872 was of great utility to navigation in shallow waters. It used a system of pulleys and wires to automatically calculate predicted tide levels for a set period at a particular location.

What did Sir William Thomson's tide-predicting machine use to function?
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A:
system of pulleys and wires