Remember Joel. Joel has the following utility function: U = HB + 2RS where HE is hiking boots and RS is running shoes. Joe] has $400 to allocate to hiking boots and running shoes. The price of a pair of boots is $80, the same as the price of a pair of running shoes. (HB on the x axis). In the last tutorial problem set, you solved for Joel's most preferred affordable bundle and re-solved for the most preferred affordable bundle when the price of running shoes increased to $100. a) Consider the change in the price of RS from $80 to $100. How much of the change in Joel's running shoe consumption is due to the income effect and what part is due to the substitution effect? b) Suppose instead of $100, the price of running shoes increased to $170. What is Joel's optimal bundle? What part of the change in consumption of running shoes is due to the income effect and what part is due to the substitution effect