Why would a confederate system of government most likely unify under central authority? to choose a state capital to form an army for defense to plan community space to build bridges and roads.

To form an army for defense

Explanation:

A confederation is a unification of nations or states that have come together to be united as a whole with a main goal in common, they usually do not want to loose power over their jurisdiction so the main reason to create a central authority is to rule them all and serve as a referee in interstate disputes, as well as to have a main representative to the whole world who is able to raise an army and defend the country.

Step-by-step explanation:

Data provided in the question

The radius of a wheel = 30 feet

Number of cars attached = 30 cars

Based on the above information

The computation is shown below:

The center angle is

The arc length is

= 1 feet

And, the area of a sector between two cars is

=

We simply do the above calculations so that each item could be find out