1. The problem is to calculate $3 \times 10^{-3} \times 600$. 2. We use the rule of exponents and multiplication: multiply the numbers and powers separately. 3. First, multiply $3$ and $600$: $$3 \times 600 = 1800$$ 4. Now multiply by $10^{-3}$: $$1800 \times 10^{-3} = 1800 \times 0.001 = 1.8$$ 5. So, the final answer is $1.8$.