The first cars with cords roll silently over the horizon in December when the Chevrolet Volt and Nissan Leaf go on sale. But for all the buzz they’re generating, electrics — and hybrids, for that matter — will remain a small portion of all

This year’s Los Angeles Auto Show Design Challenge tackles a heavy question: How do you build a lightweight car that doesn’t compromise safety, styling or performance?

Mercedes-Benz’s answer to that question