Which statement is true of succession? A. Succession happens all the time, and sometimes we can see it.
B. Succession happens rarely, and scientists can sometimes measure it.
C. Succession happens sometimes, and scientists can rarely measure it.
D. Succession happens occasionally, and we can always see it.

A. Succession happens all the time, and sometimes we can see it.

Explanation:

Succession is a usually predictable and sequential series of changes to a community that occurs over time. The exceptions to this predictability include climate change or an invasive species causing the succession.

answer: 21

step-by-step explanation:

divide 630 by 30. 30 goes into 630 21 times