A “South America’s economic powerhouse” (lines 11-12) = the economic powerhouse of South America.
B “traditionally inward-looking family-owned affairs” (lines 31-32) = affairs owned by traditional families who look inwards.
C “the world’s second-biggest mining company” (line 34) = a mining company that is the second biggest one in the world.
D “third-largest maker of civilian aircraft” (line 35) = a civilian aircraft maker that is the third largest one.
E “newly discovered offshore fields of oil and natural gas” (line 45) = fields of oil and natural gas that are offshore and that have been newly discovered.