. If you buy something in the shop on the corner when you know that the same item could have beenbought more cheaply two miles up the road in the supermarket, is your behaviour irrational?Explain.AnswerNot necessarily. If you could not have anticipated wanting the item and if it would cost you timeand effort and maybe money (e.g. petrol) to go to the supermarket, then your behaviour is rational.Your behaviour a few days previously wouldhave be irrational, however, if, when making out yourweekly shopping list for the supermarket, a moment’s thought could have saved you having to makethe subsequent trip to the shop on the corner.Are there any goods or services where consumers do not experience diminishing marginal utility?AnswerVirtually none, if the time period is short enough. If, however, we are referring to a long timeperiod, such as a year, then initially as more of an item is consumed people may start ‘getting moreof a taste for it’ and thus experience increasing marginal utility. But even with such items,eventually, as consumption increases, diminishing marginal utility will be experienced.If Darren were to consume more and more crisps would his total utility ever (a) fall to zero; (b) becomenegative? Explain.AnswerYes, both. If he went on eating more and more, eventually he would feel more dissatisfied than ifhe had never eaten any in the first place. He might actually be physically sick!