Acell begins to send out in correct chemical signals to neighboring cells during which phase of the cell cycle did the cause of the change most likely happen?

S-Phase of the cell cycle

Explanation:

All the cells send chemical signals during the S phase of the cell division. Basically in this phase of cell cycle, the cell synthesizes and replicates DNA. It is the phase that occurs during the inter phase of the cell cycle just before the  mitosis or meiosis.

The cell in the s phase communicates this to its neighboring cells in order to prepare them too for cell division.

That the ocean will absorb more CO2

Explanation:

Look, global warming is all a giant misuderstanding. Look up Gregory Wrightstone. Explains it all like you're five.