Respuesta :
[tex]\bf \textit{how much is }\frac{1}{100}\quad of \quad 10^{20}?\implies \stackrel{\textit{one hundredth}}{\cfrac{1}{100}}\cdot 10^{20}\implies \cfrac{1}{10^2}\cdot 10^{20}
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10^{-2}\cdot 10^{20}\implies 10^{-2+20}\implies 10^{18}
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1,000,000,000,000,000,000~grains[/tex]