An example of an unbalanced force is a. a bridge. b. a roller coaster going down the first drop. c. a tug of war game in which no one wins. d. a car parked in a garage.

car parked is balanced since it's not moving or anything. A bridge is also the same. It's like constant and balanced on both side. A tug of war game where nobody wins is like it's balanced between the two teams and nobody wins. Only a roller coaster going down is not balanced since it's moving downward as a result of not being balanced. Answer is b

like poles repel so keep pushing north to north and repels funny to see this

the entire statement is true and correct.  

there's no diagram, nothing is illustrated, and no question is asked.