Introduction:
To calculate the electric field at a point equidistant from two charges, we'll use the principle of superposition. According to this principle, the electric field at a point due to multiple charges is the vector sum of the electric fields due to each individual charge.

Given information:
Charge at point A = 1000 microcoulomb
Charge at point B = 1000 microcoulomb
Distance between the charges (AB) = 2m
Distance from the charges to the point where electric field needs to be calculated = 4m

Calculating the electric field due to each charge:
1. Electric field due to charge at point A:
The electric field due to a point charge is given by Coulomb's law:
E = k * Q / r^2
where E is the electric field, k is the electrostatic constant (9 x 10^9 Nm^2/C^2), Q is the charge, and r is the distance between the charge and the point where electric field is being calculated.
Plugging in the values, we get:
E_A = (9 x 10^9 Nm^2/C^2) * (1000 x 10^-6 C) / (4m)^2

2. Electric field due to charge at point B:
Similar to the calculation for charge A, we get:
E_B = (9 x 10^9 Nm^2/C^2) * (1000 x 10^-6 C) / (4m)^2

Calculating the net electric field:
Since the point where electric field is being calculated is equidistant from both charges, the electric fields due to each charge will have the same magnitude but opposite directions. Therefore, the net electric field at the point will be the vector sum of the individual electric fields.

The electric field is a vector quantity, so we need to consider both magnitude and direction. In this case, since the magnitudes of the electric fields due to each charge are equal, the resulting electric field at the point will be zero. This is because the electric fields due to the two charges will cancel each other out.

Conclusion:
The electric field at a point equidistant from two charges of 1000 microcoulomb each, placed 2m apart, and at a distance of 4m from each charge, is zero.