WINNIPEG – The Canadian dollar stayed below the United States 80 cent mark on Friday. As of 8:47 a.m. CDT, the loonie was at US$0.7943 or US$1=C$1.2590, compared to US$0.7954 or US$1=C$1.2572 when markets closed on Thursday. Crude oil was higher on Friday, but is still set for its biggest weekly decline since March. Brent