Step 
<u>find the mass of a single washer</u>
Divide the total mass by the number of washers


Step 
<u>Convert kg to mg</u>
we know that

so

therefore
<u>the answer is</u>

Answer:
A.
Explanation:
It would be A. because the question is asking how the harmful chemicals have an effect on the environment. This answer also proves that even though we don't mean to harm the environment it still happens because we are using these chemicals for things in our daily life.
Answer:
Hydronium ion concentrations increase with decreasing pH values. So, the solutions with the lower pH values have the higher H₃O⁺ concentrations.
Explanation: