Question

A pergunta esta na imagem !

Answer 1

$\dfrac{12 * 10^-^1 * 10^-^4 * 10^9}{3 * 10^-^1 * 10^4} \\ \\ \\ \dfrac{12 * \dfrac{1}{5^7} * \dfrac{1}{2^5} * 10^9}{3 * \dfrac{1}{10} * 10^4} \\ \\ \\ \dfrac{ \dfrac{3}{5^7 * 2^5 } *10^9}{ \dfrac{3}{10} * 10^4 } \\ \\ \\ \dfrac{2^4 * 3 * 5^2}{2^3 * 3 * 5^3} \\ \\ \\ \dfrac{1200}{3000} \\ \\ \\ => \dfrac{5}{2}$

Answer 2

$\frac{12^{}\times10^{-3}\times10^{-4}\times10^9}{3\times10^{-1}\times10^4} \\ \\ \frac{12^{\div3}\times10^{-3}\times10^{-4}\times10^9}{3^{\div3}\times10^{-1}\times10^4} \\ \\ \frac{4\times10^{-3-4+9}}{10^{-1+4}}\\ \\ \frac{4\times10^{2}}{10^{3}}\\ \\4\times10 ^{-1}\\ \\ \frac{4^{\div2}}{10^{\div2}} \\ \\\boxed{\therefore~ \frac{2}{5} }$

Alternativa D