The earth wouldn’t have an atmosphere
Answer: The precipitate formed is 
Explanation:
A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid or precipitated form are represented by (s) after their chemical formulas.
A double displacement reaction in which one of the product is formed as a solid is called as precipitation reaction.
The balanced chemical equation is:

I’m guessing it would be A because the river discharge tends to gather near coastlines where the river ends
In a food chain, energy is passed through one link to another. When a herbivore eats only a certain fraction of the energy, (which comes from the food) it becomes new body mass; the rest of the energy is lost as waste or used up by the herbivore in order to carry out its life processes (ex. movement, digestion, reproduction). It doesn’t necessarily threaten the plants survival, there’s also a benefit. When a animals poops out the fruit (defecate) in another area those seeds get carried to new places with the help of a dab of fertilizer and a little bit of moisture. They also help supply nutrients when they die and decompose.