Thank you for the opportunity to help you with your question! I shall do my best to help you out!

I’m assuming this is
for statistics class of some sort. This looks like a right-tail critical value
for a chi-squared distribution.

There should be a
table that was given to you in class, or in your textbook. Look under 0.005 (confidence
level of 99% is 0.005 because: 100- 99 =
1% = 0.01. It usually is a/2, therefore, 0.01/2 = 0.005).

And 18 (18 comes
from the sample size of 19, however, the degrees of freedom is always: degrees
of freedom (df) – 1) in this case it will be 19 -1.

If we look under
0.005 and 18, we should find a value of 37.156. This is assuming that ‘a’ =
0.005, if ‘a’ equals 0.01, we can just relocate the number on the chart.

I hope this answers your question.

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