While staying in lisbon, portugal, you decide to visit the cities of coimbra and viseu. you will begin and end your trip in lisbon. the following table shows the costs associated with traveling to and from each of these three cities. all costs are given in euros (€).

origin and destination
cost (€)
lisbon to coimbra
70
lisbon to viseu
53
coimbra to lisbon
37
coimbra to viseu
72
viseu to lisbon
52
viseu to coimbra
47

using this table, determine whether it is more cost-effective to go to coimbra first or to go to viseu first, and how much cheaper doing so is than the alternative.
a.
going to viseu first is €57 cheaper than going to coimbra first.
b.
going to viseu first is €17 cheaper than going to coimbra first.
c.
going to coimbra first is €57 cheaper than going to viseu first.
d.
going to coimbra first is €17 cheaper than going to viseu first