VIII.1. The road from Gostivar to Kicevo consists of horizontal sections, ascents, and descents. A cyclist travels this road, with a speed of $10 \mathrm{~km}$ per hour on the horizontal sections, $8 \mathrm{~km}$ per hour on the ascents, and $16 \mathrm{~km}$ per hour on the descents. The cyclist takes 6 hours to travel from Gostivar to Kicevo, and 5 hours to return. If the total length of the horizontal sections is $17.5 \mathrm{~km}$, determine the length of the road between the two cities.