Answer: 9.70%
Step-by-step explanation:
The formula to find the percentage error is given by :-

Given : Actual mass of zinc oxide used by pharmacist = 28.35 g
Estimated mass of zinc oxide used by pharmacist =31.1 g
Now, 
i.e. 
i.e. 
Hence, the percentage of error on the basis of the desired quantity.= 9.70%
Answer:
x = 9
y = 15
Step-by-step explanation:
x = 9
y = 15
I'm not sure how to explain this, but one side is equal to its opposite side in a parallelogram.
Hope this helps :)
<span><u>1/3x - 1/2y = 1</u>
At the 'x' intercept, y=0 , and the equation is 1/3 x = 1
Multiply each side by 3 : <em>x = 3 </em> <== the x-intercept
At the 'y' intercept, x=0, and the equation is -1/2 y = 1
Multiply each side by 2 : - y = 2
Multiply each side by -1 : <em> y = -2 </em> <== the y-intercept
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