On-air challenge: You'll be given a category, and you name something in the category starting with each of the letters in the word "Croat." For example, if the category were "boy's names," you might say Chris, Roger, Otto, Adam and Terry.
Last week's challenge: Think of a word in which the second letter is R. Change the R to an M, and rearrange the result. You'll get the opposite of the original word. What is it? (Hint: The two words start with the same letter.)
Answer: "Prose" and "poems"
Winner: Paul Keller of Lompoc, Calif.
Next week's challenge: Draw a regular hexagon, and connect every pair of vertices except one. The pair you don't connect are not on opposite sides of the hexagon, but along a shorter diagonal. How many triangles of any size are in this figure?
If you know the answer to next week's challenge, submit it here. Listeners who submit correct answers win a chance to play the on-air puzzle. Important: Include a phone number where we can reach you Thursday at 3 p.m. Eastern.