Sum1 plz help me & explain it ! thank you :)

What are the possible rational zeros of [tex]f(x) = x^4+2x^3-3x^2-4x+18[/tex]

On saturday a souvenir shop had 125 customers.sixty four percent of the costumers paid with a credit card. how many costumers paid with cash?

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. how many hours after the truck's departure will the two meet?