# Question #40a6a

##### 2 Answers

256 milligrams

#### Explanation:

If we convert 64kg to milligrams, there is 64, 000, 000 mg of person (a funny concept!) as there are 1 million milligrams in a kilogram.

So, if there are four parts for each million, and there are 64 million grams, then there will be

Hope this helps; let me know if I can do anything else:)

#### Explanation:

The average concentration of

Let's convert the units of the concentration from

We need to find the mass of

So let's set up a ratio using this information:

Multiply both sides by

Therefore, the mass of