Why does January and July have different average high temperatures

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

Can someone me? i need to have this done as soon as possible! i'm putting 20 points on this!

In the von thunen model of agricultural land use, what is produced closest to the city epicenter? a. dairy, vegetables, and fruits b. field crops, such as corn and wheat c. beef and other animal products d. wood and lumber