A student is taking a​ multiple-choice exam in which each question has two choices. Assuming that she has no knowledge of the correct answers to any of the​ questions, she has decided on a strategy in which she will place two balls​ (marked Upper A and Upper B​) into a box. She randomly selects one ball for each question and replaces the ball in the box. The marking on the ball will determine her answer to the question. There are four ​multiple-choice questions on the exam. Complete parts​ (a) through​ (d) below. a. What is the probability that she will get four questions​ correct? nothing ​(Round to four decimal places as​ needed.)