## ECON0028: The Economics of Growth Term 2 (Spring 2022)

### ASSIGNMENT 2 增长经济学代写

1.How is population growth incorporated into the Solow model? Why does the model predict that countries with higher population growth rates will have lower steady-state income per capita?

2.For each of the following scenarios, use the graphical depiction of the Malthusian model to illustrate what happens to a country’s population size and per-capita income in the short run and in the long run.  增长经济学代写
(a)Scientists discover a new strain of wheat that can produce twice as much grain per acre.
(b)A war kills half of the population
(c)A volcanic eruption kills half the people and destroys half the land.

### 3.Suppose that there are two countries, X and Y, that differ in both their rates of investment and their population growth rates.  增长经济学代写

In Country X, investment is 20% of GDP and the population grows at 0% per year. In Country Y, investment is 5% of GDP, and the population grows at 4% per year. The two countries have the same levels of productivity A. In both countries, the rate of depreciation, δ , is 5%. Use the Solow model to calculate the ratio of their steady-state levels of income per capita, assuming that α = 1/3. 增长经济学代写

4.Consider the Solow model with population growth, as presented in the text. Assume that the population can grow at two different rates n1 and n2, where n1 > n2. The population growth rate depends on the level of output per capita (and therefore the level of capital per capita). Specifically,population grows at rate n1 when k < and slows down to rate n2 when k ≥ . Draw a diagram for this model. Assume that (n1 + δ) > f( ) and that (n2 + δ) < f( ). Explain what the diagram says about the steady state of the model.