Oil prices fell to below $85 a barrel Friday in Asia as investors tried to make sense of a week of sharp zigzags in the equity and commodities markets. Benchmark oil for September delivery was down $1.01 to $84.71 a barrel at midday Singapore time in electronic trading on the New York Mercantile Exchange. Crude rose $2.83, or 3.4 percent, to settle at $85.72 on Thursday. In London, Brent crude was down 54 cents to $107.48 per barrel on the ICE Futures exchange.