Based on the nebular theory, which of these is a step in the formation of a new planetary system?

a) evaporation of water
b) nuclear fission of gases
c) repulsion of gaseous masses
d) change of gases into liquids

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.

for step 7 table c on the lab "newtons law of action"   the average time it took the car to travel .25 meters   was 1.92 seconds.

the average time it took the car to travel 0.50 meters was 2.61 seconds

hope this : )