16GPS determines position using signals from:ASatellitesBMagnetic polesCBenchmarksDRadio towers onlyView AnswerDiscussWorkspaceReportSaveEasy
17A theodolite is used to measure:AOnly distancesBHorizontal and vertical anglesCAreasDOnly levelsView AnswerDiscussWorkspaceReportSaveEasy
18Reduced level (RL) is the elevation of a point with respect to:AThe previous pointBThe instrumentCA datum (usually mean sea level)DThe groundView AnswerDiscussWorkspaceReportSaveEasy