What are the first set of lines that make up the global grid system

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

Which factors add to the greenhouse effect and are caused by human activities?

Match the following items. 1 1 (4,4) 2. (-4,-2) 3. (3.-6) 4. (-4, 6) 5. (1,5)