The weighted average of a penny is = 67.9g
<h3>Calculation of average weight</h3>
The sample of penny for pre 1982 is a total of = 18 pennies.
The mass of each penny for pre 1982 = 3.1
Therefore the total weight for penny for pre 1982
= 18×3.1
= 55.8
The sample of penny for post 1982 is a total of = 32 pennies.
The mass of each penny for post 1982 = 2.5
Therefore the total weight for penny for post 1982
=32×2.5
= 80
The weighted average
= 55.8+80/2
= 135.8/2
= 67.9g
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Iron rusts when in contact with water.
Answer:
Bacteria can evolve quickly because they reproduce at a fast rate.
Explanation:
Bacteria can evolve quickly because they reproduce at a fast rate. Mutations in the DNA of bacteria can produce new characteristics. A random mutation might cause some bacteria to become resistant to certain antibiotics, such as penicillin.
To separate it you would use a type of powder or corn starch
Zn → Zn²⁺ + 2e⁻
zinc is oxidized