L.A.-area gas prices have fallen for five consecutive weeks - not exactly a plunge, mind you, but perhaps just enough to notice the next time you fill up. The government's latest survey has the average price of regular at $4.482, down from $4.541 the previous week. Unfortunately, oil prices are back over $131 a barrel, up $2.26 for the day. That's still $16-some-odd bucks lower than the record-high prices earlier this month.