The statement which accurately described trade in the Byzantine Empire was that Byzantine merhants were able to trade ivory and exotic spices from Africa and India - these things made the Byzantine empire an important trading hub; together with its interesting location.
The earlier years of the middle ages began with the fall of the western roman empire.

a - 7 < <span>

a - 9 Give the fractions a common denominator. (2 and 3 both go into 6)
</span>

a - 7 <

a - 9 Subtract <span>

a from both sides
-7 < </span><span>

a - 9 Add 9 to both sides
</span>2 < <span>

a Multiply both sides by 6 to cancel out the fraction
12 < a Flip the inequality to make it easier to read
a > 12</span>