North and south america have been physically connected for the last

answer: the ocean

explanation: if you map out 30 n and 40 n latitude, you will get the ocean

ww1 weapons: tank. tanks were used for the first time in the first world war at the battle of the somme. they were developed to cope with the conditions on the western front. the first tank was called 'little willie' and needed a crew of 3.