How did eratosthenes measure the size of the earth

How do ocean currents affect temperature? check all that apply. they carry cold water from the poles to the equator and cool air over land. they flow north and then south below the equator. they flow south and then north above the equator. they move warm water from the equator to the poles and heat air over land. they move east to west and create prevailing winds. they move west to east and create seasonal winds.

What are the answers for the following questions?

In the 1400s, portugal’s economy was based on a. industry b. exports c. finance d. trade