What was the major difference between the voyage of the Portuguese explorers and Columbus?

In their competition for power nations raced to

What do most climatologists see as a major cause of rising global temperatures? a. earth's closer proximity to the sun due to its gravitational pull b. greenhouse gases produced by burning fossil fuels c. rising ocean levels caused by melting polar ice sheets d. water pollution cause by industrial waste

By july of 1950 north korean forces had pushed south korean forces as far south as