Question: In the ancient Western world, incense was one of the first commodities transported long distances. It grew only in the south of the Arabian Peninsula (modern-day Yemen, known then as Arabia Felix), which was transported by camel to Alexandria and the Mediterranean civilizations, notably the Roman Republic. As the republic expanded into a richer and larger empire, the demand for incense grew and planters in Arabia added a second and then a third annual crop (though this incense was not as high in quality). Cultivation also crossed to the Horn of Africa (modern-day Oman) even though such fields were farther away from Rome.2

a. How does the lower quality of the additional annual crops illustrate incense as an increasing cost industry?

b. How does the added distance of incense grown in the Horn of Africa illustrate incense as an increasing cost industry?

c. It's more costly to grow incense in Eastern Africa than in Arabia Felix. Which region would you expect to see more incense grown in?