Which of the following best explains why soil conservation is important to human agriculture? a. erosion prevention prevents millions of dollars in damage from mudslides. b. it is easier to prevent the degradation of old soil than it is to generate new soil. c. if the soil salinity gets too high crops will not be able to grow in it. d. soil contamination is a hazard to human and animal health.

Agroup of students is studying convection currents. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other in an area with warm air. after 10 minutes, the balloons are released from a height of 1 meter. which of the following do the students most likely observe? question 8 options: the cold balloon expands and rises. the warm balloon shrinks and sinks. the balloons rise at the same rate. both balloons are the same size. the ballons both rise. the cold ballon is larger than the warm balloon. the warm balloon expands and rises. the cold balloon shrinks and sinks.

About how many years does it take for one cycle of surface water to become deep water and then surface water again in the oceans? 101001,000

What process decreases the salinity of ocean water? decreased precipitationdecreased melting of glaciersincreased evaporationincreased runoff from rivers