问题
单项选择题
Assume a discrete distribution for the number of possible sunny days in Provo, Utah during the week of April 20 through April 26. For this discrete distribution, p(x)=0 when x cannot occur, or p(x)＞0 if it can. Based on this information, what is the probability of it being surely on 5 days and on 10 days during the week5 Days of Sunshine 10 Days of Sunshine（）①A. A positive value Infinite ②B. Zero Infinite ③C. A positive value Zero
A. ①
B. ②
C. ③
答案
参考答案：C
解析：
The probability of it being sunny on 5 days during the week has some positive value, but the probability of having sunshine 10 days within a week of 7 days is zero because this cannot occur.