Economics (Elasticity)

From most elastic to most inelastic:

1. an extra ball point pen
2. a mcdonald hamburger
3. a bottle of water
4. a bottle of water while stranded in a hot desert

The extra ball point pen is most elastic because of its low necessity as you already have excess of it and you can easily switch to substituting products. A McDonald's hamburger is less elastic than the extra ball pen because we our demand for food is quite inelastic as it is necessary for our survival even though we can choose to purchase substitues such as Burger King hamburgers. A bottle of water is even more inelastic because results from previous researches show that we can survive without food for a few days but we'd die in a faster rate without water. We may choose to buy other drinks such as orange juice as a substitute but the high necessity of drinks makes it more inelastic when compared to McDonald's burger. And when we're in a hot desert, there would be even less substitutes available and thus a bottle of water while stranded in a hot desert is most inelastic.