Question 12: A +8.00 point charge is at the origin. A 6.0C point charge is at :L' = 1.5 n1, on the 9: axis. \"Where on the 1:: axis is the electric eld 0? Question 13: At a certain point \"P, the electric eld due to a nearby proton is: E = (3.9, 2.2,0) N/C How far away is the proton from point 73? Question 14: Let's approximate a neuron's axon as a long charged line, with charge-per-length -4.5x10-16 C/m. What is the mag- nitude of the electric field 8.0 um from the axon? (a) 0.17 N/C (b) 0.50 N/C (c) 1.0 N/C (d) 1.3 N/C (e) 2.0 N/C