$4\mathrm{.}24.$ Mode Choice$-$express bus lane. An express bus lane is introduced on the new expressway between Zones $3$ and $1,$ making the total transit travel time only $7\mathrm{.}1$ minutes, instead of $15\mathrm{.}0$ minutes.

Estimate the transit and auto mode shares between Zones $3$ and $1$ after the expressway and express bus service are in operation. Use the MNL model and the auto and bus utility functions that were used in Example $4\mathrm{.}15.$