<span>Based on the experience of the responder, to correctly calculate measurements in real-world. Firstly is to avoid errors as much as possible. Errors are what makes your measurement invalid and unreliable. There are two types of error which is called the systematic error and the random error. Each error has different sources. Words that were mentioned –invalid and unreliable are very important key aspects to determine that your measure is truly accurate and consistent. Some would recommend using the mean method, doing three trials in measuring and getting their mean, in response to this problem.</span>
A. It does not retain the properties of the substances that make it up
Answer:
1)Na2O
let the valency of Na is x
2(x)+(2)=0
2x+2=0
2x=-2
x=-1
2)ZnO
let the valency of Zn is x
x+2=0
x=-2
3)Al2O3
let the valency of Al is x
2(x)+3(2)=0
2x+6=0
2x=-6
x=-3
4)MgO
let the valency of Mg is x
x+2=0
x=-2
If there is chloroplasts it’s a plant
