San FranciscoThe Economic Times Apple Inc, facing a tight US consumer-spending environment, is gearing up for a one-day sale on Friday and at least one analyst expects the company to offer discounts of up to 15 percent. The day after Thanksgiving, known as Black Friday, is the traditional kickoff to the US holiday shopping season and one of the biggest buying days of the year for consumers. The outlook for the computer and consumer electronics industry is universally grim, with shoppers widely expected to cut back on purchases as a recession...