Shawn said that you can use the properties of operations to solve the problems shown using mental math only. Identify the strategy that Shawn used for each problem. Then, evaluate the expression. Please help im stuck on this

Find the magnitude, correct to two decimal places, made by each of the following with positive direction of the x axis a) y= x the answer is 45° but i don’t know how

Need asap. solve for the following inequality

There are three bags: a (contains 2 white and 4 red balls), b (8 white, 4 red) and c (1 white 3 red). you select one ball at random from each bag, observe that exactly two are white, but forget which ball came from which bag. what is the probability that you selected a white ball from bag a?