Question

What is the electric flux through the surface a1 that encloses all three objects?

Answer 1

For the answer to the question above, I assume that the question is two objects, O1 and O2 have charges +1.0 µC and -1.9 µC, respectively, and a third object, O3,?two objects, O1 and O2 have charges +1.0 µC and -1.9 µC, respectively, and a third object, O3, is electrically neutral.
From Gauss's law: 
Flux = ∫c E . dA = q/eo 

Since this surface encloses all 
charge, we can simplify: 

Flux = (q1+q2+q3)/eo 
Flux = 
( (1*10^-6)+(-1.9*10^-6)+(0) )/(8.85*10^-12) = -101694.92 N·m2/C