A new spectroscopic method for the simultaneous determination of several metals in an alloy (Dutch: legering) is tested with three different reference samples. For each metal, four replicate measurements are taken. The results are gathered in the table. Note that a given s.d. is always the s.d. of individual measurements and not the s.d. of the mean (unless it is made clear that the given s.d. is the s.d. of the mean of course...).

  Ni Pb Zn
Mean 0.0530 0.103 32.48
s.d. 0.0008 0.012 0.10
True 0.0517 0.106 32.20

Is there a systematic error in the Ni analysis?
There is at the 95% percents confidence level, but not at the 99% level.
Nope, everything seems fine.
Yes, at both the 95% and 99% percent intervals there is a systematic error.