The figure is not visible in the prompt, so the exact circuit cannot be reconstructed directly from the text alone. Since this is an integer-type circuit question and the stored answer is given as $8$, I must check whether there is enough information to independently derive the current.

1. Given data

   • All resistances are $1\,\Omega$.
   • The current is of the form $I=\frac{a}{5}\text{ A}.$
   • Stored correct answer says $a=8$.

2. Issue with the problem statement For a current-electricity network problem, the circuit diagram is essential. Without the figure, there is no unique way to determine the equivalent resistance, current division, or the requested current $I$.

3. What can be inferred If the current is written as $I=\frac{a}{5}\text{ A},$ and the stored answer is $a=8$, then the corresponding current would be $I=\frac{8}{5}\text{ A}.$

4. Comparison with stored answer Because the circuit figure is missing, I cannot independently verify the value from first principles. However, taking the provided stored answer at face value gives: $a=8.$

So the answer consistent with the stored key is: $\boxed{8}$