1)which planets exhibit the greenhouse effect due to gas trapped in the atmosphere? a) mercury and mars b) venus and earth c) jupiter and saturn d) uranus and neptune 2) cause(s) empty space to expand and gravitational pull to weaken. a) black holes b) dark energy c) nebulae d) novae 3) how are newton's laws related to kepler's laws of planetary motion? a) newton proved that kepler's laws were not true b) kepler used newton's laws to create his own set of laws that only relate to planets c) newton showed that kepler's third law could be applied to any object orbiting another object d) kepler showed newton how to use his laws of planetary motion to describe motion on earth 4) the explosion and death of a high mass star is called a a) heavy element fusion b) supernova c) nova matter ejectioin d) helium flash 5) smaller objects in the solar system can collide with earth, causing a) erosion b) impact craters c) weathering d) earthquakes