<h3>A. Some or all have been united at different times.</h3>
Answer: 'A' is the response.
Explanation: The diagram A appears to show a location where magma is rising as a result of an upwelling convection current in the magma, which could cause the sea bottom to spread. The spreading of the crust is indicated by the arrows. This will become a focal point for the spreading marine floor.
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Answer:
On a weather map a barometric pressure of 055 is shorthand for 55mb.
Answer:
Many oil rich nations in the middle east must import fresh water this is due to the reason that all the natural resources are not present in a particular region. Each region as different degree of natural resources . Hence places with oil mines have spares water resources and hence need to import water instead of oil.