How is London solving traffic problems?

Gold is not now being extracted from seawater. why not? a. it would be too disruptive to marine life to develop any marine mineral resources b. there is no gold in seawater c. we don't know how to extract minerals from seawater d. it would be too costly and difficult to separate the small amount of gold from the very large amounts of halite and other minerals

Where is the only location in the united states where you drive on the left side of the road?

Where does the availability of water pose the greatest problem