1. From the n-integers 1,...,n, take two numbers arbitrarily succcessively without putting back, and find the probability that the second number taken is greater than the first number. 2. There are m (more than or equal to 3) white balls and n black balls in a bag, one ball is missing and its color is unknown. Now, randomly take two balls from the bag, the result is a white ball, find the probability of losing a white ball..