Answer:
The force between the charges when the separation decreases to 0.7 meters equals 126.955 Newtons
Explanation:
We know that for two point charges of magnitude
the magnitude of force between them is given by

where
is constant
is the separation between the charges
Initially when the charges are separated by 2.4 meters the force can be calculated as

Now when the separation is reduced to 0.7 meters the force is similarly calculated as

Applying value of the constant we get

Thus 
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