Which of the following events gave the first humans the ability to migrate from Asia to America? A.
the invention of the wheel
B.
the invention of the boat
C.
the rise of ocean levels due to climate change
D.
the uncovering of a land bridge that connected the two continents

there are hundreds of postives ways to unite a country with another country here are a   few

1 peace treaty's peace treatys

are basically a document signing a allliance with one country and another.

2 gift

what i mean by this is for example how the french gave the americans the statue of libery a gift of peace.

the lines on a surface map are called isobars. isobars are lines of constant pressure which are measured in units called millibars. the numbers indicate the amount of air pressure, in millibars, that each line represents.