8. (15 points) Calculating Rewards for an Agent When calculating rewards for an agent, there are only two ways to define utilities, there are only two ways to define utilities as given below. Utility is the sum of additive or discounted) rewards. Additive utility: 1 U([ro, ri, r2,...]) = ro tri+r2+... = Discounted utility: U([ro, r1, r2,...]) = ro + yri+ y2r2... = a) Calculate utilities U([1, 2, 3]) for additive utility and discounted utility for y=0.5. b) Why is it better to use discounted utility when calculating rewards for an agent