bill: there is an american stretch of highway today where you can drive 85 miles per hour, and it is legal. some argue it is not smart. but casey siegal is live in mustang ridge, texas, near austin, texas. how do they reach 85? why the number? reporter: everything is bigger in texas. why are for speed limits going to be the fastest? in all seriousness, the state department settled on 85 miles per hour for the new toll road. because it is a brand-new, wide open stretch of road. 41 miles, to be exact, between two very busy cities, austin and san antonio. the current choice is interstate 35 to get to and from there. it is very congested and the speed limits are not that high. so now, state highway 130 runs parallel to interstate 35 and it