<h2>Energy </h2>
Explanation:
 Energy flows in only one direction through an ecosystem
- The Sun supports most of Earth's ecosystems
- Plants create chemical energy from abiotic factors that include solar energy and chemosynthesizing bacteria create usable chemical energy from unusable chemical energy
- The food energy created by producers is passed to consumers, scavengers, and decomposers
- Energy flows through an ecosystem in only one direction, it is passed from organisms at one trophic level or energy level to organisms in the next trophic level
- Most of the energy at a trophic level – about 90% – is used at that trophic level and organisms need it for growth, locomotion, heating themselves, and reproduction
- So animals at the second trophic level have only about 10% as much energy available to them as do organisms at the first trophic level
- Animals at the third level have only 10% as much available to them as those at the second level
 
        
        
        
Answer:
Earth Science 101: Earth Science has been evaluated and recommended for 3 semester hours and may be transferred to over 2,000 colleges and universities. Expert instructors present this material in an easy-to-follow manner, and lessons are accessible at all times, from any device, so you can study at your own pace as you get started on your degree
Explanation:
Hope this helps you :)
 
        
             
        
        
        
Runoff in neighborhoods can be a problem because as the water runs it can collect pollutants such as oil, pesticides, bacteria, etc. These pollutants can end up in our drinking water or can run into our fishing supply and even our swimming water... I wouldn't want to be swimming or eating fish that was swimming in pesticides and bacteria. 
        
             
        
        
        
The correct answer is cold fronts