Observable matter makes up about what percentage of the universe?

Which statement describes john tuzo wilson’s contribution to the theory of plate tectonics? he proposed that plates carry parts of the seafloor. he theorized that pieces of earth move for a limited time. he suggested that the asthenosphere is broken into segments. he observed seafloor cracks similar to existing cracks in the continents.

Which outcome is not caused by gravitational forcea. gas and dust come together to form a planet b. planets orbit a star c. two atoms come together to form a molecule d. stars cluster to form a galaxy

How can studying economics us make better choices about how to use scare resources