Which soviet union leader brought major changes?

gorbachev
khrushchev
brezhnev
kosygin

the answer to fill in the blank in this question would be the word resource, it is defined as the money, material or people (since human resource is a very valuable good) that a company or a person has at disposition (meaning they can use the resource as they see fit), to be able to complete a task or achieve a goal.  

answer; andrew jackson approved nullification by signing it into law,and john calhoun opposed it saying it was unconstitutional;

benito

: ) hava a nice day