Error in reactor.txt (p.25) #8

Bottom of page 25 on using pipes has the command:
$ head -1 reactor.txt | tail -1
This gives line 10 of reactor.txt which is a blank line.
It should be:
$ head -11 reactor.txt | tail -1
or reactor.txt should be edited to have line 2 or 3 removed.

https://github.com/physics-codes/examples/blob/master/filespace/people/l/lisemeitner/fission/applications/power/reactor.txt