The weights of 4 boxes are 30, 20, 60 and 70 kilograms. Which of the following cannot be the total weight,in kilograms, of any combination of these boxes and in a combination a box can be used only once?
A ceramic pottery unit hires 8 craftsmen by paying each of them Rs 900 per day. The 9th craftsman demands Rs 950 per day. If this craftsman is hired then all other craftsmen must be paid Rs 950. The marginal resource (labour) cost of the 9th craftsman is _________.
In a certain town, ST Bazaar is the only option for people to buy groceries. A healthy marketplace is characterized by competition and not monopoly. Which conclusion follows the given statements?