Golfers Delight was to hold a summer spectacular event during which a celebrity golfer would be autographing golf bags for anyone purchasing the Pro Spirit line of clubs. To prepare for the event, the buyer purchased 15 additional sets of clubs to be priced at $400. There were already 10 sets of the clubs in stock but they were repriced from $350 to $400 for consistency. The event was very successful and all of the clubs sold. What was the additional markup percent earned on the clubs already in inventory? What was the total net sales on all clubs during the event?