ऐसी वस्तुएँ जिनका एक-दूसरे के बदले प्रयोग किया जाता है, कहलाती है।
The equation of demand curve is \( p \dot q = e \) \(\text{ where } p \text{ is price, } q \text{ is quantity, and }\) e \(\text{ is constant}\). What would be the shape of this demand curve?