In math, what lists can be summed into series?

More Questions:

In the video game "Darksiders', which of the Four Horsemen of the Apocalypse do you play?

Whose wife could eat no lean?

Who painted "The Boy in the Red Vest"?

What country borders Guatemala to the west?

What is the name of the instrument used for listening to the heart?

Which planet is named after the God of Love?

What famous rapper's real name is Dennis Coles?

In the TV show "The Simpsons', which character has a pacemaker?

Who has been played in a movie by both Rosemary Murphy and Jennifer Jason Leigh?

What future game show host was the first regular panelist on "Match Game "73"?

What popular fashion designer directed the music video for Bjork's "Alarm Call"?

During the prohibition era, what was sold at "speakeasies"?

What did Keats call a "season of mists and mellow fruitfulness"?

How many main islands make up the state of Hawaii?

Whose autobiography is titled "Long Walk to Freedom"?