Which of the following best illustrates the role that gravity played in the formation of our solar system? a. gravity allowed the nebula to expand and move outward. b. gravity caused the nebula to cool enough for planets to form. c. gravity removed excess gas and dust from the cores of the planets. d. gravity pulled particles of dust and gas together to form planets.

The process by which natural forces move weathered rock and soil brim one place to another is called

Speed is the ratio of the distance of an object moves to

2. which of the following statements does not accurately describe stem cells? a. embryonic stem cells make up the inner cell mass of a blastocyst. b. with more research, stem cells may be used to repair or replace damaged cells. c. the use of stem cells is without any objections since it can be used in therapies to humans. d. adult stem cells are multipotent and can differentiate into many types of cells.