Answer: 
a) 1.082 × 10⁻¹⁹C  ( e = 1.6 × 10⁻¹⁹C)   
b) 3.466 × 10¹¹ N/C
Explanation:
a)
p(r) = -A exp ( - 2r/a₀)
Q = ₀∫^∞ ₀∫^π ₀∫^2xπ p(r)dV  =  -A  ₀∫^∞ ₀∫^π ₀∫^2π   exp ( - 2r/a₀)r² sinθdrdθd∅
Q = -4πA ₀∫^∞ exp ( - 2r/a₀)r²dr = -e
now using integration by parts;
A = e / πa₀³
p(r) =  - (e / πa₀³) exp (-2r/a₀)
Now Net charge inside a sphere of radius a₀ i.e Qnet is;
= e - (e / πa₀³)  ₀∫^a₀ ₀∫^π ₀∫^2π  r² exp (-2r/a₀)dr
= e - e + 5e exp (-2) = 1.082 × 10⁻¹⁹C  ( e = 1.6 × 10⁻¹⁹C)   
b)
Using Gauss's law,
E × 4πa₀ ² = Qnet / ∈₀
E = 4πa₀ ² × Qnet × 1/a₀² 
E = 3.466 × 10¹¹ N/C 
 
        
             
        
        
        
Answer:
The decision designer is a step-wise process
Explanation:
A typical decision tree will be like this: 
Are there any forces? 
YES - then calculate the resultant forces              NO - Then no calculations are needed
IF YES - Are the forces balanced?                         NO - Then no calculations
IF YES - Then calculations can be done. 
Resolve the forces to find the resultant of the forces in the question. 
 
        
             
        
        
        
Answer:
The Sun is a natural source for visible light waves and our eyes see the reflection of this sunlight off the objects around us. 
 
        
             
        
        
        
The exact location of the 'subtropical-jet stream' is located at the North phase of 30 Degrees and the reason behind this is due to the variation of air which lies on the region of mid-altitude and warmer equatorial air. the correct answer would be Cool and Warm air masses meeting near the equator.
        
                    
             
        
        
        
Hey Dave... you need to learn and I want you to improve I believe it to be at the bottom of the hill. Please read your siht homie