How can we categorize colloids?

Which of these sequences is a geometric sequence a 1,2,4, 7, 11, 16, 22. b. 2.4.8.14.22.38 c.3.6.9. 15.18,21 d. 3,9,27,81,243,729,

What is the midpoint of np if n (1,9) and p (-5-1)

Suppose you are analyzing the relationship between time and distance given in a table,and there are 4 values for each quantity.you divide distance 2 minus distance 1 by time 2 minus time 1.you then divide distance 4 minus distance 3 by time 4 minus time 3 and get a different answer.what can you say about the relationship?