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>

57.0 is it rounded to three sig figs. You count three spaces then round from there, which would be the zero and you would round down because the four is there.
I think you mean ionic bond and not conic bond. The pair of elements that form an ionic bond are barium and chlorine.
Answer:
Explanation:
In this case the answer would be
Water is a polar molecule with positive and negative side
Now since these negative and positives are present in the water molecule . In easy terms when a substance reacts with water .the negative part of water ( oxygen ) reacts with the positive part of the substance and the positive part of the water ( hydrogen) reacts with negative part of the substance .if you look at the reason . Water is held up by one of the strongest attraction forces available .since most substances have weaker attraction forces between them ,therefore water can easily overcome them with its forces. Thus giving it the ability to dissolve a variety of substances