Question

HELP MEE PLZZZZ I DON'T UNDERSTAND THIS

Answer 1

Answer: Choice D.  $6.44 \times 10^{-4}$

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Work Shown:

We multiply the coefficients 9.2 and 7 to get 64.4, which is the same as 6.44*10^1 in scientific notation. When multiplying exponential expressions with the same base, we add the exponents

This is what the steps could look like

$\left(9.2 \times 10^{-9}\right)\times\left(7 \times 10^{4}\right)\\\\\left(9.2\times7\right)\times\left(10^{-9} \times 10^{4}\right)\\\\\left(64.4\right)\times\left(10^{-9+4}\right)\\\\\left(6.44\times 10^{1}\right)\times\left(10^{-5}\right)\\\\6.44\times\left(10^{1}\times 10^{-5}\right)\\\\6.44\times\left(10^{1+(-5)}\right)\\\\6.44\times 10^{-4}$

The final result is in scientific notation as the coefficient c is restricted such that $0 \le c < 10$