Context and question: Exposure to antibiotics early in life is associated with increased body mass in humans and mouse models. Early life is a critical period for the establishment of the intestinal microbiota and for metabolic development. Mice exposed to subtherapeutic antibiotic treatment (STAT)– with either penicillin, vancomycin, penicillin and vancomycin, or chlortetracycline had altered composition of the gut microbiota as well as its metabolic capabilities. Moreover, research have shown that mice given low-dose penicillin (1 μg/g body weight) around birth and throughout the weaning process had an increased body mass and fat mass, accelerated growth, and increased hepatic expression of genes involved in adipogenesis, compared to controlled mice. In addition, penicillin in combination with a high-fat diet increased fasting insulin levels in mice. However, it is unclear whether or not antibiotics cause obesity in humans. Studies have found a correlation between early exposure of antibiotics (<6 months) and increased body mass (at 10 and 20 months). Another study found that the type of antibiotic exposure was also significant with the highest risk of being overweight in those given macrolides compared to penicillin and cephalosporin. Therefore, there is correlation between antibiotic exposure in early life and obesity in humans, but whether or not there is a causal relationship remains unclear. Although there is a correlation between antibiotic use in early life and obesity, the effect of antibiotics on obesity in humans needs to be weighed against the beneficial effects of clinically indicated treatment with antibiotics in infancy.
Why do physicians use antibiotics on infants when the relationship has been proven? 
Answer: weighed against the beneficial effects
Context and question: At no more than 200 kilometres (120 mi) north to south and 130 kilometres (81 mi) east to west, Swaziland is one of the smallest countries in Africa. Despite its size, however, its climate and topography is diverse, ranging from a cool and mountainous highveld to a hot and dry lowveld. The population is primarily ethnic Swazis whose language is siSwati. They established their kingdom in the mid-18th century under the leadership of Ngwane III; the present boundaries were drawn up in 1881. After the Anglo-Boer War, Swaziland was a British protectorate from 1903 until 1967. It regained its independence on 6 September 1968.
When did the ethnic Swazis establish a kingdom?
Answer: mid-18th century
Context and question: Tristan is primarily known for its wildlife. The island has been identified as an Important Bird Area by BirdLife International because there are 13 known species of breeding seabirds on the island and two species of resident land birds. The seabirds include northern rockhopper penguins, Atlantic yellow-nosed albatrosses, sooty albatrosses, Atlantic petrels, great-winged petrels, soft-plumaged petrels, broad-billed prions, grey petrels, great shearwaters, sooty shearwaters, Tristan skuas, Antarctic terns and brown noddies. Tristan and Gough Islands are the only known breeding sites in the world for the Atlantic petrel (Pterodroma incerta; IUCN status EN). Inaccessible Island is also the only known breeding ground of the Spectacled Petrel (Procellaria conspicillata; IUCN Vulnerable). The Tristan albatross (IUCN status CR) is known to breed only on Gough and Inaccessible Islands: all nest on Gough except for one or two pairs who nest on Inaccessible Island.
There are 13 species of resident land birds on the islands and how many species of breeding seabirds?
Answer:
unanswerable