Answer:
14
Step-by-step explanation:
mass of 100 centimeters of copper wire is 
so, mass of 1 centimeter of copper wire will be 
hence, 14 centimeters of copper wire will provide .28 copper
1/2 gallon= .75 grams
1 gallon= 1.5 grams
2 gallons = 3 grams
4 gallons = 6 grams
So
4 gallons is 6 grams
Then we add on a half which is .75 grams
6g + 0.75g = 6.75g
Hope that helps ;•)
<span>Critical points are where the derivative is 0, i.e. where it crosses the x - axis
The Critical points lies where the derivative is 0, while it crosses the x-axis, SO, in this case the choice 3 looks like best answer for this.
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