How does chromatography work?

Match the following. match the items in the left column to the items in the right column. 1. foreshocks process used to locate the epicenter of an earthquake 2. magnitude newer magnitude scale that measures the amount of moved (displaced) rock along a fault to determine the strength of an earthquake 3. mercalli intensity scale measure of the total amount of energy released during an earthquake 4. moment magnitude scale areas on active faults where a major earthquake hasn't occurred in a long time 5. richter scale mini-quakes that usually occur before a major earthquake 6. seismic gaps scale that measures the effects or severity of an earthquake 7. triangulation scale of magnitude based on the size of seismic waves produced by an earthquake

Suppose you are estimating the size of a blue crab population. what is the population size if the number marked in the first catch is 40, the total number in the second catch is 200, and the number marked in the second catch is 50?

What material did the moon come from?