Who the hell invented the following phrases!!!

What are the meaning of the following words?

open secret
larger half
clearly confused
act naturally
alone together
Hell's Angels
found missing
liquid gas
civil engineer
deafening silence
seriously funny
living dead
Microsoft Works ( The best one !!)
military intelligence
jumbo shrimp
Advanced BASIC
tragic comedy
unbiased opinion
virtual reality
definite maybe
original copies
pretty ugly
same difference
plastic glasses
almost exactly
constant variable
even odds
minor crisis
extinct life
genuine imitation
exact estimate
only choice
freezer burn
free love
working holiday
rolling stop

The best of the lot

Great Depression
free trade
peacekeeper missile
sweet tart
crash landing
now then
butt head
sweet sorrow
student teacher
silent scream
taped live
alone together
good grief
tight slacks
living dead
near miss
light tanks
old news
hot chilli
criminal justice
peace force