What term i used for the sharing of power between a central government and state government

Federalism is the term used for the sharing of power between a central government and state government

Explanation:

United States establishes federalism to share the powers between state government and central government. In a way, federation is created in which governing rules and institutions power are shared between "national and state governments". The powers that are shared are known as "concurrent powers". Example of these powers are imposing tax, borrowing money or spending money by the government.  

During colonial times, federalism meant the urge for a stronger national government so that state government is always under the national and they do not act as per their wish.

answer; people where able to travel across the u.s.a faster than any other mode of transportation,travel time was about a week,from coast to coast