Answer:
they need the exchange so they can grow, obtain energy, and get rid of waste. It also helps to mantian a balance of amterials in the cell. 
Explanation:
 
        
             
        
        
        
In general chemistry, isomers are two or more elements that have the same number of protons but differ in mass number. In organic chemistry, the compounds are cis or trans isomers if they have the same chemical formula, but differ in the placement of functional groups based on molecular geometry. Cis isomer is when two like functional groups are on the same side of the molecules, while trans isomer is when the like functional groups are on opposite sides. 
The cis-trans isomers are shown in the picture. As you can see, in the cis isomer, the methane functional group are both in the same side. Same as well with the hydrogen atoms. On the other hand, these functional groups are opposite to each other in the trans isomer.
 
        
        
        
1000 is the answer to the queshtion
        
                    
             
        
        
        
Answer:
Imole/C=129 Directions Show All Of Your Work For Each Of The Following Problems. 1.
Explanation:
 
        
             
        
        
        
Your answer is <span>D)	The angle of light from the sun as it reflects off the moon and viewed from the Earth's surface because of the way the sun hits the moon one side has to light the other doesn't and when the moon rotates the sun hits another part of the moon.
If you need more help I would be glad to help!
</span>*~"AB84"~*