<u>Answer:</u> The concentration of
comes out to be 0.129 M.
<u>Explanation:</u>
To calculate the concentration of base, we use the equation given by neutralization reaction:

where,
are the n-factor, molarity and volume of acid which is 
are the n-factor, molarity and volume of base which is 
We are given:

Putting values in above equation, we get:

Hence, the concentration of
comes out to be 0.129 M.