D has a total of four significant figures.
Answer:
There was an improvement in accuracy. There was no change in precision.
Explanation:
<em>The average mass after recalibration is closer to the mass of the standard, </em>so the recalibration improved the accuracy<em> </em>(the measurement is closer to an accepted 'true' value).
The standard deviation did not change, so the precision (or how disperse the measurements are) was not affected.
Hope this helps!
https://youtu.be/MT5tKijKZwQ
Answer:
C. because the 4s orbital is at a lower energy level
