How did the railroad change travel for people in the country?

It made mailing letters and packages easier, and the people could go to places much faster than they usually could by horse and carriage.

observing traffic laws in exchange for driving on the highway.

both are true, the congress does have the power to create banks, even if this power is not specifically described in the constitution, since there is nothing restricting it and there is power given to the congress to make "all laws which shall be necessary and proper". maryland was not allowed to tax a branch of the national bank operating there, and the supreme court decided that no state could. both of these topics were discussed in a decision of the mcculloch v. maryland case in 1819.