challenge: What is the significance of a temperature deviation of +8°C in relation to standard day conditions?
  
  A. The air humidity is 8% lower than predicted at the measurement altitude
  B. The air is 8°C warmer than predicted at the measurement altitude
  C. The air pressure is 8 times higher than predicted at the measurement altitude
  D. The air is 8°C cooler than predicted at the measurement altitude
  Answer: 