Why does secondary succession occur faster than primary succession?

Because soil is already present.

Explanation:

primary succession if I remember this right is when there is no soil and Moss breaks down rocks into soil which can take lots of years or something similar to that but secondary succession is when soil is already present so therefore it occurs faster than primary succession

d. making up measurements to record.

i believe the correct answer from the choices listed above is the first option. the scientists need to look at the   validity of data, claims, hypotheses, and observations before  developing an argument. they base their arguments on facts that are present and they make sure they have proofs. 

explanation: