Answer:
a) 4.325*10^10 V/m
b) 1.689*10^10 V/m
c) 0
d) 6.384 C/m^3
Step-by-step explanation:
Hello!
The electric field of a sphere of uniform charge is a piecewise function, let a be the raius of the sphere
For r<a:
 

For r>a:

Since a=0.26m and k= 8.987×10⁹ N·m²/C²
 
 a) 

 E=4.325*10^10 V/m
b)

 E=1.689*10^10 V/m
c)
 Since r --> ∞  1/r^2 --> 0
  E(∞)=0
d)
The charge density may be obtained dividing the charge by the volume of the sphere:
