barbara is on the democratic line, and has been waiting to ask a question from portage, mich.. good morning. caller: good morning. thank you for c-span. i have a question about this gas tax. we have had a couple of them, two or three of them in the past, where we're going to tax the gas. and we as a people accept it, and then we see nothing being done with the roads or bridges. how can we be sure that this so- called tax is actually going to go to the road construction, and bridge repairs, instead of into the general fund where they can spend it anyway they want to spend it? guest: thank you, barbara. that is a good question. the way that the federal program is set up is that the money collected from the federal gas tax goes directly to the highway trust fund. and that is separate from the general fund. and that money as firewalls and protected. and that has over the last several reauthorization and several bills have kept that protection. that money is definitely used for highways and bridges. state to state, that can vary. estee programs differ significantly -- state programs