Elements Of Remote Sensing
Due to perturbation of the orbit, satellite orbit parameters are frequently updated on measurements carried out by its

Six ground stations
Five ground stations
Four ground stations
Three ground stations

ANSWER DOWNLOAD EXAMIANS APP

Elements Of Remote Sensing
Earth observations from a satellite platform provide:

Constant solar zenith angles and similar illumination conditions
Synoptic view of a large area
All of these
Repetitive observations of the same area with intervals of a few minutes to a few weeks

ANSWER DOWNLOAD EXAMIANS APP