Suppose that the prices of two categories of products can be explained by a bivariate normal distribution. If category A has a mean price of 10 dollars and a standard deviation of 2 dollars while category B has a mean price of 8 dollars and a standard deviation of 1 dollar. The correlation between the prices is 0.5. For a pair of products a and b randomly selected form category A and B respectively, What is the probability that the price of A is higher than 12.9 dollars given that the price of B is 10 dollars