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B) Robert Hooke
The cell was first discovered by Robert Hooke in 1665 using a microscope. The first cell theory is credited to the work of Theodor Schwann and Matthias Jakob Schleiden in the 1830s.
This scale is a device invented by American seismologists, Charles Richter and Beno Gutenberg, which is used to measure the magnitude of an earthquake.
The Richter Scale does not rate an earthquake magnitude by normal number scale because it is designed as logarithmic scale. This means that every increase in rate would mean that an earthquake rated as 3 is 10 times as strong than an earthquake which is rated as 2.
For your question, ...
The 2 difference of the 2 earthquakes accounts for the big difference in the damage cost. As it is stated above, every increase in rate of an earthquake through the Richter scale means that the energy released is ten times stronger. So, the city which was strucked by an earthquake measured as 6 on the Richter scale experienced an earthquake which is 100 times stronger than the earthquake measured as 4 in the other city.