$16.$ A train departs from City X at $6$:$00$ AM and arrives at City Y at $2$:$45$ PM$.$ How many hours did the journey take?$\mathrm{}$

$17.$ If a passenger train has $12$ carriages, and each carriage can accommodate $80$ passengers, what is its total seating capacity?$\mathrm{}$

$18.$ Calculate the kinetic energy of a $150-$ton locomotive traveling at a speed of $100$ km$/$h$\mathrm{.}\mathrm{}$

$19.$ A freight train takes $8$ minutes to cross a bridge that is $1\mathrm{.}2$ kilometers long. What is its speed in meters per second?$\mathrm{}$

$20.$ If a railway track has a curve with a radius of $300$ meters, what is the curvature in degrees?