Two highways connect an origin$-$destination pair, having performance functions of $t_1=5+4(\frac{x_1}{c_1})$ and $t_2=4+5(\frac{x_2}{c_2})$ for routes $1$ and $2,$ respectively. For the performance functions, the t$\text{'}$s are in minutes and the flows $(x^{\text{'}}s)$ and capacities $($c$\text{'}$s$)$ are in thousands of vehicles per hour. The total traffic demand for the two highways is $4000$ vehicles during the peak hour. Initially, the capacities of routes $1$ and $2$ are $3500ve\frac{h}{h}$ and $4600ve\frac{h}{h},$ respectively. A construction project is planned that will cut the capacity of route $2$ by $2100ve\frac{h}{g}.$ How much additional vehicle$-$hours of travel time will be added to the system assuming userequalibrium conditions hold?