On-air challenge: Every answer is a word containing an A and a Z. Given anagrams of the remaining letters, name the word. For example, given "leg," the answer would be "glaze".

Last week's challenge: Eight people are seated at a circular table. Each person gets up and sits down again — either in the same chair or in the chair immediately to the left or right of the one they were in. How many different ways can the eight people be re-seated?

Answer: 49

Venezuela's elections commission announced Saturday that voters will go to the polls on April 14 to choose a successor to President Hugo Chavez, who died this week after a battle with cancer.

The nation's constitution mandated that an election be called within 30 days of Chavez's death on March 5, but the scheduled date falls outside of that window. Nicolas Maduro, Chavez's vice president, was sworn in as interim leader on Friday.

The recent meteor blast in Russia has brought renewed attention to the risk posed by meteors on a collision course with Earth. NASA and the European Space Agency are working on a plan to develop a rocket that could collide with an asteroid and knock it off course. Dr. Andrew Cheng of the John Hopkins Applied Physics Lab, who is leading the initiative, talks about it with host Jacki Lyden.

The Oklahoma House of Representatives recently reached unanimous approval of measure that would wipe charges of prostitution off the criminal records of victims of human trafficking.

Alannah Selinger is one of the co-founders of the OU chapter of Freedom Movement, a Christian sex trafficking awareness group. She says she discovered her passion about non-profits and activism while in college, and has become especially enthusiastic about combating human sex trafficking.