About the Cover

The sailboard was invented by Newman Drake in the 1950s, and the sport was popularized by Californians Jim Drake and Hoyle Schweitzer in the 1970s. The sport spread rapidly from California, throughout the United States and around the world. By standing on the rudderless board and maneuvering the sail to glide along the water's surface, a sailboarder can reach speeds of up to 45 miles per hour. In Chapter 4, you will learn to solve problems involving rate, speed, and distance.

About the Graphics
Twisted torus. Created with Mathematica. A torus with rose-shaped cross section is constructed. Then the cross section is rotated around its center as it moves along a circle to form a twisted torus. For more information, and for programs to construct such graphics, see: www.wolfram.com/r/textbook.