单选题Commemorative plaques cast from brass are a
单选题从1，2，3，4，…，19，20这20个自然数中，至少任选多少个数，就可以保证其中一定包括两个数.它们的差为12。
单选题If x and y are different prime numbers, each greater than 2, which of the following must be true?Ⅰ. x+y ≠91Ⅱ. x-y is an even integer.Ⅲ. xy is not an integer.
单选题The product of a positive integer a and 1080 is a square number. What is the least value of a?
单选题100个人中，88个有电视，76个有报纸，有电视没报纸的是x个，问有报纸没电视的有多少?
单选题On a road there is a tree every 46 meters. If the trees are numbered consecutively, what is the number of the tree 5060 meters past tree number 56?
单选题PhishCo runs a number of farms in the arid
单选题Bob has 40 coins consisting only of dimes and quarters. If the number of dimes is 10 more than twice the number of quarters, what is the total value of the coins.
单选题空间10个点 最多能够构成多少条直线?
单选题Parland's alligator population has been
单选题Let’s be the set of all positive integers having at most 4 digits and such that each of the digits is 0 or 1．What is the greatest prime factor of the sum of all the numbers in S?
单选题Can the positive integer n be written as the sum of two different positive prime numbers?1 n is greater than 3. 2 n is odd.
单选题Which of the following is equivalent to x2＜3x+4?
单选题Which of the following describes the set of all possible values of the positive integer k such that，for each positive odd integer n，the value of nk is midway between consecutive integers?
单选题What is the total number of integers between 1 00 and 300 that are divisible by 3?
单选题如果n是正整数，并且n2的个位数是4，n+122的个位数是1，那么n+55的个位数是多少?
单选题某个班一共有30个学生，其中11人参加chess club，13人参加bridge club，还有10人什么也没有参加，问有多少人仅仅参加一个club?
单选题A car traveled 462 miles per tankful of gasoline on the highway and 336 miles per tankful of gasoline in the city．If the car traveled 6 fewer miles per gallon in the city than on the highway，how many