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: Dell was the first company to publicly state a timeline for the elimination of toxic polyvinyl chloride (PVC) and brominated flame retardants (BFRs), which it planned to phase out by the end of 2009. It revised this commitment and now aims to remove these toxics by the end of 2011 but only in its computing products. In March 2010, Greenpeace activists protested at Dell offices in Bangalore, Amsterdam and Copenhagen calling for Dell's founder and CEO Michael Dell to 'drop the toxics' and claiming that Dell's aspiration to be 'the greenest technology company on the planet' was 'hypocritical'. Dell has launched its first products completely free of PVC and BFRs with the G-Series monitors (G2210 and G2410) in 2009.

Answer: What toxic chemical did Dell set to eliminate from its products?

Question: Many parts of the Americas are still populated by indigenous peoples; some countries have sizable populations, especially Belize, Bolivia, Chile, Ecuador, Greenland, Guatemala, Mexico, and Peru. At least a thousand different indigenous languages are spoken in the Americas. Some, such as the Quechuan languages, Aymara, Guarani, Mayan languages, and Nahuatl, count their speakers in millions. Many also maintain aspects of indigenous cultural practices to varying degrees, including religion, social organization, and subsistence practices. Like most cultures, over time, cultures specific to many indigenous peoples have evolved to incorporate traditional aspects, but also cater to modern needs. Some indigenous peoples still live in relative isolation from Western culture and a few are still counted as uncontacted peoples.

Answer: Belize, Chile and Greenland are just some countries with sizable populations of what peoples?

Question: During the years 1940-1955, the rate of decline in the U.S. death rate accelerated from 2% per year to 8% per year, then returned to the historical rate of 2% per year. The dramatic decline in the immediate post-war years has been attributed to the rapid development of new treatments and vaccines for infectious disease that occurred during these years. Vaccine development continued to accelerate, with the most notable achievement of the period being Jonas Salk's 1954 development of the polio vaccine under the funding of the non-profit National Foundation for Infantile Paralysis. The vaccine process was never patented, but was instead given to pharmaceutical companies to manufacture as a low-cost generic. In 1960 Maurice Hilleman of Merck Sharp & Dohme identified the SV40 virus, which was later shown to cause tumors in many mammalian species. It was later determined that SV40 was present as a contaminant in polio vaccine lots that had been administered to 90% of the children in the United States. The contamination appears to have originated both in the original cell stock and in monkey tissue used for production. In 2004 the United States Cancer Institute announced that it had concluded that SV40 is not associated with cancer in people.

Answer:
When was the Polio vaccine created?