1. The frequency spectrum below was measured in the horizontal direction on one bearing cap of a large 5-blade centrifugal pump in the US. An electric motor rotating at 1760 RPM provides power to the pump through a gearbox with a gear ratio of 2.15:1, with the pump running at the lower speed shaft. For each elevated vibration, list its frequency, its order in terms of a fundamental frequency (rotational speed, line frequency, etc), and the most likely root cause of the vibration. Velocity ips 7200 Leu 3520 4090 820 1760 14400 20,000 -23,000 Frequency, CPM