Answer to Question 1
(1.) The techniques of production which are available.
(2.) The prices of inputs required by each technology.
Answer to Question 2
When total revenue is at its maximum, the demand is unit elastic and marginal revenue equals zero. However, to maximize its profit, a single-price monopolist produces so that its marginal revenue equals its marginal cost. If marginal revenue equals zero, then in order for this level of output to maximize the monopolist's profit, marginal cost also must equal zero. But marginal cost will never equal zero because to produce another unit always incurs some costs. Since marginal cost cannot equal zero, it is impossible for a profit-maximizing single-price monopolist to produce the amount of output that maximizes its total revenue.
Zhang Huan, To Raise the Water Level in a Fishpond.
Variable Gases: Water Vapor
Projections of global temperature depend heavily on the level of future greenhouse gas emissions
Kyoto Protocol encourages industry to innovate and reduce the level of emissions
A Drug’s Plateau Level
Increase in total spending in presidential campaigns, 1976-2020