Many countries in sub-Saharan Africa have very low labor productivities in many sectors, for example in manufacturing and agriculture. They often despair of even trying to attempt to build their industries unless it is done in an autarkic context, behind protectionist walls because they do not believe they can compete with more productive industries abroad. Discuss this issue in the context of the Ricardian model of comparative advantage

In the short-run, marginal costs are equal to the change in variable costs as output changes. ( mc = change in variable cost / change in quantity) assume that capital is fixed in the short-run. (a) start with the equation for marginal cost and derive an equation that relates marginal cost of production to the cost and productivity of labor. (b) draw a standard looking short-run marginal cost curve and use the equation you derived to explain its shape.