correct answer is: b) ₹768 & ₹7168

Explanation
Here,
P = ₹6400
R = 6 %
T =2 years
We know, SI\ =\frac{P\times R\times T}{100}
\therefore SI =₹\left(\frac{6400\times6\times2}{100}\right)
\rightarrow SI = ₹768
\therefore Simple interest =\ ₹768
We also know,
Amount\ =\ (Principle\ +\ Simple\ Interest)
\therefore Amount =₹6400+₹768
\rightarrow Amount =₹7168
Ans: SI = ₹768 and Amount = ₹7168.