Answer:
E = 0.0096 N/C
Step-by-step explanation:
E = I/σπr²
I = 40 mA = 0.04A
σ silver = 6.29X10⁷ /Ωm
r = 0.29 mm/2 = 0.145 mm = 1.45x10⁻⁴ m
E = 0.04A / (6.29X10⁷ /Ωm)(π)(1.45x10⁻⁴ m)² = 0.0096 N/C
*sorry, don't have time to calculate electron drift velocity for you!