The approximately 65,000 images the Surveyor orbiter has beamed home in the nearly three years it has been circling Mars are full of this kind of expected hydro-scarring. But some of the pictures took scientists by surprise. The older a formation is, the more likely it is to have been distorted over the eons--smoothed by periodic windstorms or gouged by the occasional incoming meteor. However, a few of the newly discovered water channels look flesh. That discovery has lead astonished researchers to conclude that these channels may have been recently formed. Paleontologists have long assumed that if underground water was going to bubble up on Mars, it would have to be somewhere in the balmy equatorial zones, where temperatures at noon in midsummer may reach 68 degrees Fahrenheit (20 degrees Centigrade). Almost all the new channels, however, were discovered at the planet’s relative extremes--north of 30 degrees north latitude and south of 30 degrees south latitude--and all were carved on the cold, shaded sides of slopes.
Novelty公司计划开支$65,000来上市他的最新产品。 他的研究显示10%的概率销售收入是$40,000,60%的概率是$80,000,30%的概率是$120,000。但是,在公司收到最近的经济预测后,他修改了原先的估计。现在的估计是50%的概率销售收入是$40,000,40%的概率是$80,000,10%的概率是$120,000。在修改估计的前后,公司分别应该如何决定是否推出这个新产品?()
普通型的调控设备价格是162,000元,使用寿命预计为10年;如果增加65,000元就可以购买一台耐用型的调控设备,在10年使用期中每年都可以比普通型的设备节约运营费22,000元。假设基准折现率为10%,试问那种设备更经济?