问答题正态分布中一组数的期望为3，方差为1，另一组数的期望为9，方差为2，那么数据分布在第一组数的区间1，4的概率和数据分布在第二组数的区间5，11的概率相比较结果如何?
问答题共有A，B，C，D，E 5个元素要放在有顺序的5个位置上，要求满足条件：A在B之前，B在C之前A＞B＞C，同时还要满足D在E的前面D＞E，问一共有多少种排法?
问答题某个五边形中，有四个角的度数分别为90°、65°、150°和100°，那么五个角的算术平均值与第五个角谁大?
填空题A certain college has 8,978 full-time students
填空题.If the function g is defined for all nonzero numbers y by find the value of each of the following.
填空题40. There are a total of 20 dogs and cats at a kennel. If the ratio of the number of dogs to the number of cats at the kennel is 3 to 2, how many cats are at the kennel?
填空题39. Two cars started from the same point and traveled on a straight course in opposite directions for 2 hours, at which time they were 208 miles apart. If one car traveled, on average, 8 miles per hour faster than the other car, what was the average speed of each car for the 2-hour trip?
填空题.Solve each of the following inequalities for x.
填空题 When the positive integer n is divided by 3
填空题.Which of the following statements are true?
填空题.Geometry Figure below shows two concentric circles, each with center O. Given that the larger circle has radius 12 and the smaller circle has radius 7, find the following.
填空题 The daily temperatures, in degrees Fahrenheit
填空题8. What is the value of f(x)=3x2-7x+23, when x=-2
填空题 In Geometry Figure below, AB=BC=CD
填空题For each of the following functions
填空题The numbers of passengers on 9 airline flights wer
填空题 In Geometry Figure below, AC=BC
填空题12. How many 3-digit positive integers are odd and do not contain the digit 5?
填空题.This exercise is based on the following graph.
填空题.Algebra Figure that follows shows right triangle PQR in the xy-plane. Find the following.