Given,
Price of land = Rs.640000
Rate of increase = 5% in every six month
So,
Value of plot after 2 years\(= 640000({1}+\frac{5}{100})({1}+\frac{5}{100})({1}+\frac{5}{100})({1}+\frac{5}{100})\)
\(= 640000\times\frac{21}{20}\times\frac{21}{20}\times\frac{21}{20}\times\frac{21}{20}\) = Rs. 706440.25