Why did the constitution grant congress the power to create "inferior courts”?

the builders of the constitution ensured the extension of the principle of checks and balances.
the builders of the constitution feared the supreme court would become too powerful without other courts.
the builders of the constitution wanted other branches of government to have their own courts.
the builders of the constitution wanted federal and state courts to share power under the supreme court.

for this case we have the following equation:

we apply distributive property to the terms within parentheses.

subtracting 2 on both sides of the equation:

answer: the time zones used to be whatever the local authority wanted them to be. one town might have 6am whenever the sun came up and another town had 6am 10 minutes later.  

the trains had a hard time when their orders said to be at a certain point at 6am.  

6am, but who's 6am.  

the railroads got together and set the time zones more or less along the longitude lines across the country.

explanation: