The percentage O2 by Weight in atmospheric air is____________?
The percentage O2 by Weight in atmospheric air is____________? A. 18% B. 23% C. 77% D. 79%
The percentage O2 by Weight in atmospheric air is____________? A. 18% B. 23% C. 77% D. 79%
The commercial sources of energy are____________? A. solar, wind and biomass B. fossil fuels, hydropower and nuclear energy C. wood, animal wastes and agriculture wastes D. none of the above
Due to which of the following reasons the cables should not be operated too hot ? A. The oil may loose its viscosity and it may start drawing off from higher levels B. Expansion of the oil may cause the…