Use the rule of total probability to find the indicated probability. Two stores sell a certain product. Store A has 36% of the sales, 2% of which are of defective items, and store B has 64% of the sales, 4% of which are of defective items. The difference in defective rates is due to different levels of pre-sale checking of the product. A person receives one of this product as a gift. What is the probability it is defective? Round to the nearest thousandth when necessary.