A 500 mL sample of drinking water contains 0.001 mg of mercury. How many ppb is this?

The value is  

Explanation:

From the question we are told that

   The volume of the drinking water is  

   The mass of  mercury it contains  

Generally the mass of water is mathematically represented as

Here is the  density of water with value  

So

=>    

Generally  ppb mean part per billon ,  and  1 billon is  100,000,000

So the part per billon which this represents is mathematically represented as

=>    

explanation: no but i do not usually comment

they vary. it used to be meat, grain, bread, candy, beverages, donuts, and fruits/vegetables. now they added exercise in.