$$4\times {{10}^{9}}\times 5\times {{10}^{2}}$$  $$=20\times {{10}^{11}}$$  $$=2\times {{10}^{12}}$$ 
A computer makes $$4\times {{10}^{9}}$$ operations per second. How many operations does it make in $$5\times {{10}^{2}}$$ seconds? 

A: $$4\times {{10}^{11}}$$ 
B: $$2\times {{10}^{11}}$$ 
C: $$2\times {{10}^{12}}$$ 
D: $$20\times {{10}^{18}}$$ 
E: $$2\times {{10}^{19}}$$ 