Question

what is 0.9×10 to the negative power of 1 in standard notation

Answer 1

0.09 is the answer …

Answer 2

$a^{-1}=\dfrac{1}{a}\\\\0.9\cdot10^{-1}=0.9\cdot\dfrac{1}{10}=\dfrac{0.9}{10}=\dfrac{0.9\cdot10}{10\cdot10}=\dfrac{9}{100}=0.09$