• IMD issues weather forecasts across four categories:
  Nowcasting: Up to 3 hours
  Short range: Up to 3 days (72 hours)
  Medium range: 3 to 10 days (operationally issued for 5 days in advance for Gramin Krishi Mausam Sewa bulletins)
  Long range: Beyond 10 days up to a season
• Hence, 5 days is the standard operational medium-range forecast issued twice a week (Tuesday & Friday).

• Reason (R) is true: The nominal GPS space segment consists of 24 operational satellites distributed across 6 orbital planes inclined at $55^\circ$ to the equator at an altitude of ~20,200 km.
• Assertion (A) is false: Each of the 6 orbital planes accommodates 4 operational satellites ($6 \times 4 = 24$), not three satellites.

Assertion (A) is true: Operational microwave remote sensing utilizes both active sensors (e.g., Radar, Synthetic Aperture Radar - SAR, scatterometers, altimeters) and passive sensors (e.g., microwave radiometers).

Reason (R) is false: Active microwave sensors emit their own electromagnetic energy pulses toward the target and detect the reflected backscatter. In contrast, it is passive microwave remote sensing that measures the naturally emitted thermal microwave radiation from surfaces based on emissivity and temperature.