13. Joanna has the following utility function consisting of her consumption of bagels (B) and cups of coffee (C). U(B, C)=BBC Joanna's utility-maximizing bundle is B=3 and C=1. 13.1 (6pt) Please calculate the relative price PB/Pc. 13.2 (6pt) Everything else held equal, a promotion of 50% off on all bagels is going on. Calculate the new marginal rate of substitution (MUs/MUc) at the new utility-maximizing bundle. 13.3 (6pt) Using the cross price elasticity of demand to determine whether Bagels and Coffee are complements? Substitutes? Or irrelevant for Joanna