The property of semiconductors that makes them most useful for constructing electronic devices is that their conductivity<span> may easily be modified by introducing </span>impurities<span> into their </span>crystal lattice<span>. The process of adding </span>controlled impurities<span> to a semiconductor is known as </span>doping<span>.</span>
        
             
        
        
        
Answer: Chlorophyll
Explanation: The primary pigment used in photosynthesis, reflects green light and absorbs red and blue light most strongly
 
        
                    
             
        
        
        
Answer:
<em>The total amount of energy transferred during photosynthesis for this ecosystem equals</em><em> 260,000 kcal/m2/yr.</em>
Explanation:
To answer this question, we need to know that  
- gross primary productivity (GPP) = energy captured and converted into chemical energy during photosynthesis
- net primary productivity (NPP) = difference between GPP and respiration rate
So, to calculate GPP we need to sum NPP to Respiration rate. This if,
NPP = 165,000 kcal/m2/yr
R = 95,000 kcal/m2/yr
NPP = GPP – Respiration
Then,
GPP = NPP + R
GPP = 165,000 kcal/m2/yr + 95,000 kcal/m2/yr
GPP = 260,000 kcal/m2/yr
 
        
             
        
        
        
Batteries, biomass, petroleum, natural gas, and coal are examples of stored chemical energy