Which Pixar short film featured a lonely volcano singing to find love?

Lava

In the movie "Cast Away," what brand of volleyball becomes Tom Hanks' character's companion? Which holiday do we celebrate by dressing up in costumes and trick-or-treating? What American poet wrote "Christmas Bells," the basis for the carol "I Heard the Bells on Christmas Day"? Who developed the popular farming simulator Stardew Valley? In geometry, what is a shape with all points the same distance from the center called?