1. Did this region produce gold as well in addition to producing gas?-Общий
What did this region produce as well in addition to producing gas?-Специальный
2. Does the amount of oil produced depend on the recovery method used? -О
What does the amount of oil produced depend on?-С
3. Will pipes from cold-resistant grades of steel be affected by temperatures of 50°-60° below zero?-О
What pipes will not be affected by temperatures of 50°-60° below zero?-С
4. Has the oil field always been of economic significance?-О
What significance has the oil field always been of? - C
5. Can one choose the most accurate method only by comparing it with others?-О
Only by what can one choose the most accurate method?- C
