BELOIT — Gov. Scott Walker on Tuesday signaled he’s open to charging tolls on Wisconsin’s Interstates, but with a key condition: linking it to a reduction in the state’s 30.9-cent-per-gallon gas tax. Walker also said an impasse over the state’s next transportation budget risks costly delays to billion-dollar highway projects now under construction. That includes a $1.2 billion expansion of Interstate 39-90 from the Madison area to the Illinois state line. The Interstate formed the backdrop for Walker’s remarks in a press conference at a Beloit rest stop. Republicans who control the state Assembly have proposed seeking federal approval to...