A) 33
B) 30
C) 34
D) 31
Correct Answer: A
$ \Rightarrow $ $ {{(2\times 1000)}^{10}}=1.024\times 10^{k} $
$ \Rightarrow $ $ {{(2\times 10^{3})}^{10}}=\frac{1024}{1000}\times 10^{k} $
$ \Rightarrow $ $ 2^{10}\times 10^{30}=1024\times {10^{k-3}} $ $ [\because {{(PQ)}^{n}}=P^{n}\times Q^{n}] $
$ \Rightarrow $ $ 2^{10}\times 10^{30}=2^{10}\times {10^{k-3}} $
On comparing the powers, we get $ 30=k-3 $
$ \Rightarrow $ $ k=33 $