I did slightly better in a couple of places, so probably wrong. I'll submit it now, before better solutions show up for everything. (Corrected holes 3 and 4 as per more-careful-readers-of-specs.)

# hole 1: 16
perl -le 'sub h1 {(pop=~/\w+/g)[4]}'      -e'print h1"abc   ,., de f g
+ hi jk"'

# hole 2: 20
perl -e'


goto
TPC'

# hole 3: 19
perl -le 'sub h3 {pop=~/^(.+?)\1+\z/s}'    -e'print h3 join" ",qw(hihi
+hihi)'

# hole 4: 19
perl -le 'sub h4 {split"",pack"H*",@_}'    -e'$,=$";print h4"68696C6f"
+'

# hole 5: 22  XXX see below:
perl -le 'sub h5 {$_<$x or$x=$_ for@_;$x}' -e'print h5(3,5,2,8,7)'

# hole 6: 38
perl -le 'sub h6 {grep{s/.//}sort map{/[aeiou]/;$&.$_}@_}' \
                            -e'$,=$";print h6 qw(book eel hi huge i pe
+a wrap)'
[download]

oopsdate: Yes, 5 doesn't work w/o priming the temporary (which makes it 30 chars).
So, here's an overly golfish version that I managed to trim to 32:

perl -le'sub x {$_[-1]<$_[0]?pop:shift;$#_?&x:@_}' -e'print x(-3,-5,-2
+,-8,-7)'
[download]

(And yes, by the time I posted them, the solutions were all pretty much established. jmcnamara said he wasn't posting answers for a week, so it's a guess between not posting 'spoilers' and getting 'rep' -- especially when others are updating as you collect and cut and paste.  --  Anyway, it is kinda neat that, at least for these first few, the straightforward solutions are the best.)

  p

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