On the occlusal surface of a u type mandibular second premolar, the "u" pattern is due to the form of the:
(1) central groove and lingual groove.
(2) buccal ridge.
(3) ml and dl cusps.
(4) central groove and buccal triangular grooves.
(5) transverse ridge.

How does the slope of the land affects the speed of lava flow

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

Using complete sentences, explain the differences between a command economy and a market economy. what type of economic system is created when these two systems are combined? what are the benefits of combining these two systems?