The exchange of new items and thoughts empowered financial development. The one impact of the Columbian trade is the acquaintance of new sustenances with both Europe and the Americas. A noteworthy effect of the Columbian Exchange on Western Europe was the presentation of is new sustenance trims that enhanced the European slim down.
The mercantilist policy was created by England in the 17th century around the mid 1650s, in which basically they imported raw materials from the colonies to process it and transform into manufactured products to be later sold to other countries, creating a new way of trading.
A policy or attitude of letting take their own course, without interfering. In better words: the government has very little regulation in the economy.
There wouldn't be a USA, and...
the Indians would still have pretty much all of the Middle-west of the USA.
Hawaii would still be under their kings/queens
Alaska would still be part of russia
China would pretty much never had any technological progress (they isolated themselves)
Japan would still be going around with pretty much katanas.
etc etc
if you want more i can give you more (if you want information on why one is on the list, post it in the comments)
hope this helps
B) computer, because the space program required equipment that could perform very complicated calculations.