Business Green: Solar PV manufacturer First Solar last week posted fourth quarter financial results showing higher-than-expected profits, but still saw its shares fall over seven per cent on Friday after profit margins narrowed and its outlook for 2010 left investors underwhelmed. The company reiterated its existing forecast for 2010 net sales of $2.7bn (£1.75bn) to $2.9bn and earnings per share of $6.05 to $6.85. However, its Nasdaq-listed shares had rallied in the days prior to the earnings …