Prices on shares in selected power companies and in companies with largetrading activity in electricity:April 21Company Closing price Change in % VolumeSTOCKHOLM (SEK)Arise Windpower 53,00 0,47 60 826Eolus Vind 42,50 2,41 36 216Holmen 198,00 0,00 899Stora Enso 58,50 0,43 20 818COPENHAGEN (DKK)Vestas Wind Systems 340,90 -0,35 1 562 075HELSINKI (EUR)Fortum 18,58 -0,64 1 699 812Stora Enso 6,10 2,18 4 708OSLO...