1. would be D
2.would be B
Here something that might help
<span>
Most scientists believe that for half of </span>Earth's<span> 4.6-billion-year history, the</span>atmosphere<span> contained almost no </span>oxygen<span>. Cyanobacteria or blue-green algae became the first microbes to produce </span>oxygen<span> by photosynthesis, perhaps as long ago as 3.5 billion years ago and certainly by 2.7 billion years ago.</span>
The micro tubes that form prophase and control chromatids are called spindle fibers.
Answer:
C
Explanation:
The definition of biotic potential is the maximum reproductive capacity of an organism under optimum environmental conditions.
