$V_{GR}=V_{E}P.$

At present $P=$$$15$ per carload for freight over this segment.

a$.$ Consider the possibility of adding $1,2,$ or $3$ more trains per day.

maintaining the same train lengths. Predict the equilibeium flows and

the corresponding costs and revenues for these strategies. Which of

and why?

b$.$ If your objective were maximum servise to users, which would

you recommend, and why? Compare with your answer to part and

discuss.

c$.$ For a given frequency, what are the advantages and disadvantages

of varying train lengths? If you knew that for a frequency $O^{**}$ the de$-$

mand would be $V,$ what train length would you recommend?

d$.$ Consider these alternative strategies: $T^4=(Q^4=3,L^4=75),$

$T^{\text{'}}=(4,75),T^6=(5,75),T^2=(4,70),T^2=(5,70),T^2=(5,60).$