Guardian: The French power group EDF yesterday submitted a firm all-cash offer to buy British Energy, emerging as the sole bidder for Britain’s main nuclear power producer. The state-owned group is believed to have offered closer to 600p than the 700p a share originally talked of. Last night EDF also confirmed it had bought land next to two nuclear power plants in Britain – a move seen in France as preparing for a defeat in the BE bidding. It wants to build up to four of the possible 10 …