**Electric Field and Charges:**

The electric field is a vector quantity that describes the force experienced by a charged particle due to the presence of other charges in its vicinity. The electric field is created by a charged object and can exert a force on any other charged objects within its influence.

Charges can be positive or negative, and like charges repel each other, while opposite charges attract each other. The magnitude of the electric field at a point in space is given by the equation:

\[E = \frac{ kQ }{ r^2 }\]

where E is the electric field, k is the electrostatic constant (equal to \(9 \times 10^9 Nm^2/C^2\)), Q is the charge creating the electric field, and r is the distance from the charge.

**Calculating the Electric Field:**

In the given problem, we have two charges: Q1 = \(1.6 \times 10^{-19} C\) and Q2 = \(6.4 \times 10^{-19} C\). The distance between them is r = 0.3 m.

We need to find the point where the electric field is zero. This means that the forces exerted by the two charges on a test charge at that point will cancel each other out.

Let's assume that the electric field at this point is zero. At this point, the electric field due to Q1 and Q2 can be calculated using the formula mentioned earlier.

Electric field due to Q1: \(E_1 = \frac{ kQ_1 }{ r_1^2 }\)
Electric field due to Q2: \(E_2 = \frac{ kQ_2 }{ r_2^2 }\)

**Setting up the Equations:**

Since the electric field is a vector quantity, the magnitudes of the electric fields due to Q1 and Q2 must be equal for them to cancel each other out. Therefore, we can set up the following equations:

\(E_1 = E_2\)

\(\frac{ kQ_1 }{ r_1^2 } = \frac{ kQ_2 }{ r_2^2 }\)

Substituting the given values, we get:

\(\frac{ (9 \times 10^9)(1.6 \times 10^{-19}) }{ r_1^2 } = \frac{ (9 \times 10^9)(6.4 \times 10^{-19}) }{ r_2^2 }\)

Simplifying the equation, we find:

\(\frac{ r_2^2 }{ r_1^2 } = \frac{ 6.4 \times 10^{-19} }{ 1.6 \times 10^{-19} }\)

\(\frac{ r_2 }{ r_1 } = \sqrt{ \frac{ 6.4 \times 10^{-19} }{ 1.6 \times 10^{-19} } }\)

\(\frac{ r_2 }{ r_1 } = 2\)

This means that the ratio of the distances from Q1 and Q2 to the point where the electric field is zero is 2:1.

**Conclusion:**

From the calculations, we can conclude that the point where the electric field is zero is located 0.