Simplify Scientific Notation: 10×10^-3×10^5 Multiplication Problem

To simplify the equation $10 \times 10^{-3} \times 10^5$, we will apply the exponent multiplication rule which states that when multiplying like bases, we add the exponents.

• Step 1: Identify exponents on each term - The base for all terms is $10$.
• Step 2: The expression can be rewritten using implied exponents:
  $10^1 \times 10^{-3} \times 10^5$
• Step 3: Apply the rule of exponents. When multiplying terms with the same base, add the exponents:
  $10^{1 + (-3) + 5}$
• Step 4: Calculate the sum of the exponents:
  $1 + (-3) + 5 = 3$
• Step 5: Rewrite the expression with the summed exponent:
  $10^3$

Therefore, the simplified expression is $10^3$, which is choice 4.