3 × 1012 is 5 × 1014 times as great as 6 × 10-3, indicating option A is the correct answer.
When comparing two numbers expressed in scientific notation, we can find how many times greater one number is than another by dividing the first by the second. Let's calculate how many times as great 3 × 1012 is compared to 6 × 10-3.
Divide:
(3 × 1012) ÷ (6 × 10-3) = (3/6) × (1012 ÷ 10-3)
= 0.5 × 10(12 - (-3))
= 0.5 × 1015
= 5 × 1014
Therefore, 3 × 1012 is 5 × 1014 times as great as 6 × 10-3.