Answer:
26m/s
Explanation:
Assuming that the acceleration is constant, we can start by calculating the train speed when it's free of the congested area:
[tex]a = \frac{\deltav}{\deltat} = \frac{12 - 5}{8} = \frac{7}{8} = 0.875 m/s^2[/tex]
Then with the same acceleration we can find out the final speed:
[tex]v = v_0 + at = 12 + 0.875*16 = 26m/s[/tex]