21.Find all possible arrangements that can be made by taking 4 letters of the word "VIDYAMANDIR" 22. The positive value of K for which co-efficient of x4 in the expansion of (1 + x) is 6 is. 23. Number of points of discontinuity of f(x) = [2x2] in [1,2) is, where [x] denotes integer less than or equal to x. 24.A pair of fair dice is thrown independently 3 times. The probability of getting a score of 7 exactly twice is P. Find 72 P. y 3 25. The distance between x - + = 0 and 2xy + 4 = 0 is a, and distance between 3 2 2 x+= 0 and 3x - 3 + 15 = 0 is , then find a + . y - 2 == 2 2 2