Question: 2cheap and economic low cost
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Answer: 2-cheap and economic (low cost)

Question: The observed change in storage practice over the period 1990 to 2003 has increased the mean annual CH4 emission by 3090 mostly due to changes in the amount of manure being stored
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Answer: The observed change in storage practice over the period 1990 to 2003 has increased the mean annual CH4 emission by 30-90%, mostly due to changes in the amount of manure being stored.

Question: We recommend to upgrade to postgresql94 to get the full set of fixes
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Answer: We recommend to upgrade to postgresql-9.4 to get the full set of fixes.

Question: Counted in a census in Voldby Denmark
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Answer:
Counted in a census in Voldby, Denmark