How do i complete this with quadratics?

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

Fa bus driver leaves her first stop by 7: 00 a. m., her route will take less than 37 minutes. if she leaves after 7: 00 a. m., she estimates that the same route will take no less than 42 minutes. which inequality represents the time it takes to drive the route, r?

Aproduction manager test 10 toothbrushes and finds that their mean lifetime is 450 hours. she then design sales package of this type of toothbrush. it states that the customers can expect the toothbrush to last approximately 460 hours. this is an example of what phase of inferential statistics