Question

(9⋅10

Answer 1

Answer:

  A. -18·10^6

Step-by-step explanation:

The rules of exponents apply to powers of 10 used in scientific notation. The associative and commutative properties of multiplication also apply.

Application

  (a^b)(a^c) = a^(b+c)

The numerical product is ...

  $(9\cdot10^9)\cdot(-2\cdot10^{-3})=(9)(-2)(10^{9-3})=\boxed{-18\cdot10^6}$

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Additional comment

Expressed in scientific notation, the result would be ...

  $-1.8\cdot10^7$

Your calculator can perform this multiplication for you.