Accuracy describes how well a measuring instrument determines the variable it is measuring. How close the value is to real value. The level of accuracy of measuring tool determines the detail to which it can measure. In order to be accurate in their work scientists need first select a measuring instrument that allows an appropriate measure of accuracy and then to calibrate it. Calibrating an instrument involves measuring already known quantities to check how accurately it is. In the laboratory accuracy of a test is determined when possible comparing results from the test in question with results geenrated from an established reference method.
Likely to be a poisonous nuclear power plants waste would concern her of her own health issues and family and Community
Explanation:
Hydrogen atoms contain 1 proton and 1 electron while being devoid of neutrons. When they lose their electron they form an ion or H+, a particle carrying a unit of positive charge. pH measures how basic or acidic a water-based solutions are, with a formula for pH is
pH = -log[H+].
...where pH is -base 10 log of the concentration of hydrogen ions within the solution.
Initial volume= 20 mL
Final volume= 600 mL
# of dilutions=
= 30
for a pH 2= [H+]= 
∴ [H+]= 
and pH is an antilog of [H+]= - log 
∴pH = 3.47
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Answer:
The correct answer is option B, that is, an endoskeleton evolved to enclose the dorsal nerve cord, which develops from the notochord.
Explanation:
It has been discovered that the ancestors of the modern-day fish were vertebrate chordates. The vertebrate chordates are considered to have evolved from the invertebrate chordates that are identical to the present day tunicates. It has been found that in vertebrates the endoskeleton has evolved to encompass the dorsal nerve cord that has been developed from the notochord (a characteristic of invertebrates).