Got this question incorrect and no matter how hard i try i can't figure it out!

The right answer is the third option:

10^-3 L / 1 mL

That conversion factor may be derived from 1 L = 1000 mL

=> 1 L / 1000 mL = 1

=> 10 ^ - 3 L / 1 mL = 1

So, you can mutilply by the conversion factor 1 * 10^ -3L / 1 mL because it the equivalent to 1.

The other options are not valid. Let's see why:

1 KL = 1000 L => 1KL / 1000 L = 1

=> 10 ^ - 3 KL / 1 L, which is contrary to the first option.

In that same way you can find the righ conversion factors that relate L with cL, and L with d and you will discard the other options.

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