老舊機器故障的間隔時間已知服從一個具有平均數25 小時的指數分配。這部機
器剛被修復過。決定從現在起到下一次發生故障超過50小時的機率。

Apsychologist has developed a series of personality inventories and wants to determine if they are valid. one of the scales measures perfectionism, so he asks a colleague for advice on how to establish the validity of this scale. the colleague tells him that if he were to find a sample of people with personality disorder, these people would obtain high scores on a scale that measures perfectionism.

Does this sound good? hey great britain, we need to talk. we’ve been through a lot these past couple of years and i don’t think that i would’ve made it this far without you but, i think it’s time that i tried to. don’t get me wrong, i think you’re a pretty great country! you’re smart, you’re funny, you're rich, and very dominant but, these past couple of years you’ve been a little too dominant. as each year goes by you become more and more self-absorbed. you’re only concerned about your own well-being. for example, when we get into arguments you always raise the taxes on paper and tea prices; it just isn’t fair. not only are you selfish but, you always want your buddies around. it’s not very fun cleaning up after you and your british soldiers (you guys never put the toilet seat down). they’re always popping up unexpected, and you always force me to let them stay for a couple of days. not to mention how irresponsible you are. i don’t like it when you force some of your responsibility on me. it’s not my fault that you got yourself into another war so, why should i have to pay for it? listen, in the beginning, what we had was good but, you and i aren’t so compatible anymore. i think it’s best if i took some time to be independent and think for myself for once. -yours truly, the states

The tea party movement is a. an official third party that challenges both democrats and republicans in national elections. b. an organized challenge to incumbents in the republican party by the most conservative wing of the republican party. c. an organized challenge to incumbents in the democratic party by the most liberal wing of the democratic party. d. an offspring of the green party that runs for state and local office in many midwestern states. e. the now defunct party that gave way to the republican party at the end of the “second party system.”