At a school's open house, T-shirts and sweatshirts were sold. Each item was purchased by either a student or a parent. The two-way frequency table summarizes a random sample of 70 items sold that night. Student Parent T-shirt Sweatshirt Let T-shirt be the event that an item randomly chosen from among those sold was a T-shirt, Let parent be the event that an item randomly chosen from among those sold was purchased by a parent. Find the following probabilities, Write your answers as decimals. (a) P(parent) = (b) P(T-shirt and parent) = (c) P(T-shirt | parent) = X