All of the following are independent variables a market researcher may use in a marketing experiment except.
a) price
b) distribution outlet
c) free samples
d) unit sales
e) product color

answer; i believe the correct answer is (form utility); good luck

answer; foreign exchange transaction;

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.