Four Students ran a mile in PE class. Each student’s mile time is listed below.

Acourgette seed and a pumpkin seed is planted p(courgette seed germinates) 4/5 and p(pumpkin seed germinates) = 1/6 what is the probability that both seds germinate

Of the ones listed here, the factor that had the greatest impact on the eventual destruction of native americans' ways of life was the development of the a) automobile. b) highway. c) railroad. d) steamboat.

[10 points, algebra 2]according to my answer key the restrictions are -1 and 4. but why not positive 1?