What is the relationship between air temperature and its density? hurry !

Which statement explains what upwelling causes? a. upwelling causes tides to rise and fall. b. upwelling causes changes in the direction of currents. c. upwelling causes nutrients, minerals, and tiny organisms to rise. d. upwelling causes currents in the pacific ocean to change direction. i think the answer is c.

If a volcano’s magma is high in silica, the volcano will probably a. erupt quietly. b. remain dormant. c. erupt explosively. d. produce dark-colored lava.

Who developed the theory of plate tectonics?