1.the blank of solar system formation is grounded in the idea that dust grains form clumps of matter that collide and slowly accumulate until they are planetary size.
a. condensation theory
b. expulsion theory
c. collision theory
d. fragmentation theory
2. what do all of the jovian planets possess that none of the terrestrial planets does?
a. natural satellites
b. water vapor
c. solid cores
d. numerous moons and ring systems

Cladistics is a way of classifying organisms by examining the characteristics of their ancestors and descendants and depicting the relationships in a cladogram. which of the following best describes a challenge in classifying organisms this way? a. there are millions of species on earth, and a cladogram is not a practical means for classifying all of them. b. it is impossible to tell which organisms are most closely related to each other using a cladogram. c. cladograms are detail-oriented and do not provide a useful understanding of evolutionary relationships. d. there is a limited number of ways to organize the information, so most cladograms end up looking very similar.