This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
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Question: The major settlements in the ceremonial county are concentrated on the Fylde coast (the Blackpool Urban Area), and a belt of towns running west-east along the M65: Preston, Blackburn, Accrington, Burnley, Nelson and Colne. South of Preston are the towns of Leyland and Chorley; the three formed part of the Central Lancashire New Town designated in 1970. The north of the county is predominantly rural and sparsely populated, except for the towns of Lancaster and Morecambe which form a large conurbation of almost 100,000 people. Lancashire is home to a significant Asian population, numbering over 70,000 and 6% of the county's population, and concentrated largely in the former cotton mill towns in the south east.

Answer: Where are the major settlements in the ceremonial county located?


Question: The printed circuit board industry defines heavy copper as layers exceeding three ounces of copper, or approximately 0.0042 inches (4.2 mils, 105 μm) thick. PCB designers and fabricators often use heavy copper when design and manufacturing circuit boards in order to increase current-carrying capacity as well as resistance to thermal strains. Heavy copper plated vias transfer heat to external heat sinks. IPC 2152 is a standard for determining current-carrying capacity of printed circuit board traces.

Answer: What's the minimum amount of copper a layer in a PCB can have to be considered "heavy copper"?


Question: Other microscopic procedures may also aid in identifying infectious agents. Almost all cells readily stain with a number of basic dyes due to the electrostatic attraction between negatively charged cellular molecules and the positive charge on the dye. A cell is normally transparent under a microscope, and using a stain increases the contrast of a cell with its background. Staining a cell with a dye such as Giemsa stain or crystal violet allows a microscopist to describe its size, shape, internal and external components and its associations with other cells. The response of bacteria to different staining procedures is used in the taxonomic classification of microbes as well. Two methods, the Gram stain and the acid-fast stain, are the standard approaches used to classify bacteria and to diagnosis of disease. The Gram stain identifies the bacterial groups Firmicutes and Actinobacteria, both of which contain many significant human pathogens. The acid-fast staining procedure identifies the Actinobacterial genera Mycobacterium and Nocardia.

Answer:
What do almost all cells readily stain with?