Bạn tham khảo :
a.
$10^2 = 10.10 =100$
$10^3 = 10^2 .10 =100.10 =1000$
$10^4 = 10^3 . 10 = 1000 .10 =10000$
$10^5 = 10^4 .10 = 10000 .10 =100000$
$10^6 = 10^5 .10 =100000.10 =1000000$
b .
$1000=10^3$
$1000000 = 10^6$
$\underbrace{10.10.10......10}_{12} =10^{12}$