September 20, 2013 - 4:25PM Stocks to watch on the Australian stock exchange at close on Friday: BHP - BHP Billiton - down 29 cents, or 0.79 per cent, at $36.39 Resources giant BHP Billiton says its new US$1.5 billion gas plant will supply 20 per cent of the domestic West Australian market amid hopes of doubling capacity. FLT - FLIGHT CENTRE - down $1.25, or 2.51 per cent, at $48.55 Flight Centre is altering its name to as Flight Centre Travel Group to highlight that it offers more than airfares. SYD - SYDNEY AIRPORT - up six cents, or 1.5 per cent, at $4.06 The number of travellers through Sydney Airport rose by 2.4 per cent in August to 3.2 million, with strong growth in visitors from India, China and Malaysia.