What is in the freezing cold water in Scandinavia that nourishes such an affinity for sunny pop melodies? Nina Persson’s blase affect on “Lovefool” makes it one of the great anti-love songs, a summery blast from a group of Swedes, and the high note hit by Norway’s Morten Harket on “Take On Me” is a laser that could cut steel. Fun fact: this chapter not only features three Scandinavian acts but four Jacksons! (Although one of them has no relationship to the famous siblings, and one is just a band name.)