Soil compaction results from

a. the reduction or elimination of pore space in soil
b. the weight of heavy machinery on soil
c. livestock walking over soil
d. all of the above

Which statement correctly describes other ways in which nebulae and stars are different? a. a star always has a higher density than a nebula. b. stars can form inside a nebula but a nebula can never be produced by any star. c. stars can never form inside a nebula but a nebula can be produced by any star. d. a nebula always has a higher density than a star. reset submit