Task: Question Generation
Input (English): Passage: Air temperature is stable over the year at 26 °C in February and 27 °C in August. Precipitation is as high as 3,000 mm/year and mostly occurs in summer. Sea currents are south-easterly and easterly in winter and south-westerly and westerly in summer. The average surface water temperature is 26-28 °C in February and 29 °C in May. The water temperature is constant at 4.8 °C at the depths of 1,600 m and below. Salinity is 31.5-32.5‰  in summer and 30.0-33.0‰ in winter in the southern part. In the northern part, it decreases to 20-25‰ due to the inflow of fresh water from the Irrawaddy River. Tides are semidiurnal  with an amplitude of up to 7.2 meters.
Output (English): How many percentage points differentiate the salinity in water from the lowest in summer to the highest in winter?