A standard contains a known amount of a substance. If u are performing an experiment you will use a sample with a known concentration to create a standard curve (a straight line). Positive and negative controls are measured against the standard curve to show the expected results if the sample u will be testing is positive or negative.
I'm going to have go with TRUE
dna fingerprints or the teeth
<u>I think around the age of 13-15. Although, some may say thats the worst time I dont think so. They will never learn anything if you dont let them try. How will they lve on their own if they dont know the challenges ahead of them. Yes, age DOES NOT always matter. BUT you could trust an 8-year-old to do things you may ask more than a 13 year old. Its more so matters how the childs obediance levels are and the household. It depends, for example, my 19 year old sister. I trust my 8 year old brother more than her. Lying, sneaking, and all those things make me decide. </u>
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<em>None of this was copied and pasted!!!</em>
Hope this helps!
Have a great day!
Good luck!
- Hailey: D
