Thank you, Mr. Chair.
I'll turn to new rail cars. I don't know—I'm not an engineer who designs rail cars—but presumably there are constraints to redesigning rail cars. If you change the thickness to be thicker, you add weight to an individual car. Looking at the new DOT-111s for example—even the old ones, for that matter—how much latitude is there to add thickness before weight becomes a problem with respect to the rail and the railbed? I presume there isn't a whole lot of tolerance there. In other words, what I'm driving at is this. How many designs are possible for rail cars, to improve the safety, given that there may be constraints with respect to weight on a rail?