Which competition did Keri Herman win a silver medal in “Slopestyle” and is held in Tignes, France?
Keri Herman:  She won a silver medal in "Slopestyle" at the 2011 Winter X Games XV in Aspen, Colorado, behind Kaya Turski. Winter X Games Europe: The Winter X Games Europe is an annual sports event - the European edition of the Winter X Games - held in Tignes, France.
Winter X Games Europe