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The consensus among linguists is that modern, standard Czech originated during the eighteenth century. By then the language had developed a literary tradition, and since then it has changed little; journals from that period have no substantial differences from modern standard Czech, and contemporary Czechs can understand them with little difficulty. Changes include the morphological shift of i to ej and e to i (although e survives for some uses) and the merging of i and the former eji. Sometime before the eighteenth century, the Czech language abandoned a distinction between phonemic /l/ and // which survives in Slovak.
What kind of differences do writings from the past have from modern Slovak?
A: unanswerable

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The density of paper ranges from 250 kg/m3 (16 lb/cu ft) for tissue paper to 1,500 kg/m3 (94 lb/cu ft) for some speciality paper. Printing paper is about 800 kg/m3 (50 lb/cu ft).
What is the range of paper dryness?
A: unanswerable

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The company aims to reduce its external environmental impact through energy-efficient evolution of products, and also reduce its direct operational impact through energy-efficiency programs. Internal energy-efficiency programs reportedly save the company more than $3 million annually in energy-cost savings. The largest component of the company's internal energy-efficiency savings comes through PC power management: the company expects to save $1.8 million in energy costs through using specialized energy-management software on a network of 50,000 PCs.
What does Dell aim to increase by creating energy efficient products?
A: unanswerable

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Throughout its prehistory and early history, the region and its vicinity in the Yangtze region was the cradle of unique local civilizations which can be dated back to at least the 15th century BC and coinciding with the later years of the Shang and Zhou dynasties in North China. Sichuan was referred to in ancient Chinese sources as Ba-Shu (), an abbreviation of the kingdoms of Ba and Shu which existed within the Sichuan Basin. Ba included Chongqing and the land in eastern Sichuan along the Yangtze and some tributary streams, while Shu included today's Chengdu, its surrounding plain and adjacent territories in western Sichuan.
What was Sichuan referred to as by ancient Chinese sources?
A:
Ba-Shu