Comair has slashed its fleet, flights and workforce in the last seven years. Delta said the smaller regional planes are expensive to fly because they are not as fuel-efficient and cost more to maintain as the fleet ages.___ By The Associated Press(equals) The Dow Jones industrial average rose 187.73 points to 13,075.66. The Standard & Poor's 500 jumped 25.95 to 1,385.97. The Nasdaq composite index rose 64.84 to 2,958.09. Benchmark U.S. crude added 74 cents on Friday to finish at $90.13 per barrel in New York. Brent crude, which sets the price for oil imported into the U.S., added $1.21 to end at $106.47 per barrel in London. In other futures trading, natural gas prices fell by 9.5 cents to end at $3.01 per 1,000 cubic feet. Heating oil added 2.1 cents to finish at $2.89 per gallon, while wholesale gasoline rose 7.4 cents to end the week at $2.89 per gallon.