You visit a new town in the summer and see a person dressed as a duck juggling plastic ice cream cones on the street. this piques your curiosity. you walk toward the duck person and see she is advertising the mallard ice cream shop. you decide to go in and see what kind of flavors a shop named mallard would offer. this is an example of a marketing strategy that:

the correct answer is b.)

answer: marginal utility of the fourth brownie is 0.

explanation: marginal utility is the addtional utility gained from the consumption of one more unit of a good. it is given by,

so, marginal utility at the 4th unit will be given by

since, the values are not given here, you can simply find marginal utility at fourth unit by subtracting total utility at 3rd unit from total utility at 4th unit.