Mamma Mia! The ABBA Quiz

French-Canadian Celine Dion won the contest for Switzerland in 1988, which launched her international career.

Swedish tax laws at the time allowed stage costumes to be tax-deductible as long as they couldn't be considered street wear. "Nobody can have been as badly dressed on stage as we were," Björn said in "ABBA: The Official Photo Book."

"Fernando" was originally released by Frida before ABBA became a group. The original lyrics featured a friend consoling Fernando, who has lost his love. The revised lyrics are about two freedom fighters from the war between Mexico and Texas, according to Björn.

Only half the tunes on this disc had charted somewhere in the world. But thanks to the addition of "Fernando," the album went multiplatinum around the globe.

Although they deny this, it is widely believed that "The Winner Takes it All" is about Björn and Agnetha's divorce. Considering the content of the lyrics (which he wrote), the fact that she sung the vocals and they did get divorced around that time, you can understand the skepticism. (The other couple, Frida and Benny, divorced in 1981).

Lasse Hallström, who directed many ABBA videos and their feature-length film "ABBA: The Movie" went on to greater fame as director of "What's Eating Gilbert Grape" and "Cider House Rules."

This one should be easy. "Dancing Queen" went to No. 1 in more than 12 countries and was ABBA's only No. 1 hit in the U.S. Its first live performance was at a pre-wedding gala for King Carl XVI Gustaf and Queen Silvia of Sweden. No doubt Queen Siliva could identify with the tune.

This 1994 Australian movie featured an awkward girl who was obsessed with weddings and ABBA's music.

Jukebox musicals, where all the music in the show is from one popular group or singer, had existed before "Mamma Mia" but this play was the one that made the trend explode.