A factor used in retrospective premium calculations. It is a percentage of the standard premium and is used to provide the insurer with up-front money for administrative expenses. The Basic Premium Ratio, a percentage, is generally found in the retro manual of the plan being used. Retrospective plans, otherwise known as retros, are claim sensitive workers compensation rating programs specifically designed and used when an employer is of the size required to justify its use.
Q: In which order will seismic waves from an earthquake arrive? A. P waves, S waves, L waves B. L waves, S waves, P waves C. P waves, L waves, S waves D. S waves, P waves, L waves. A: P waves, S waves, L waves is the order of the seismic waves in which an earthquake arrives. baby_SJ01|Points 310|.
Earthquakes generate three types of seismic waves: P (primary) waves, S (secondary) waves and surface waves, which arrive at seismic recording stations one after another. Both P and S waves penetrate the interior of the Earth while surface waves do not. Due to this, P and S waves are known as body waves. Surface waves arrive last and are the least interesting to seismic tomographers because they don't penetrate deep inside the Earth, therfore provide little information about inacessible terrain. Click on the image to see an enlarged version.