John will need to sleep for 10.3 hours before his second exam so that the
average of his two exam scores is an 80.
We were given
8 hours of sleep = 70
To get average of 80
<u>70+ x</u> = 80
2
Cross multiply:
70+x = 160
x= 160-70
= 90.
If 8 hours of sleep = 70
x hours of sleep = 90
Cross multiply
8× 90 = 70 × x
720 = 70x
x = 720/70
x = 10.2857
≈ 10.3 hours of sleep
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Answer:
Many other power plants like coal-fired power plants have cooling towers or these large bodies of water as well. This similarity exists because the process of turning heat into electricity is almost identical between nuclear power plants and coal-fired power plants.
Explanation:
The phrase which best describes a period on the periodic table is: a row of elements
Periodic table can be defined as an organized tabular arrangement of all the chemical elements arranged in order of increasing atomic number or number of protons, especially in rows.
On a related note, chemical elements with the same number of valence electrons are found in the same column of the periodic table.
In conclusion, the rows of a periodic table are referred to as periods while the columns are referred to as groups.
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