a) Capital is variable: The total supply of land cannot be changed, whereas the supply of
capital can be increased or decreased. If the residents of a country
produce more or save more from their income, and these savings are
invested in factories or capital goods, it increases the supply of
capital.
b)Capital is more mobile: Of all the factors of production, capital is the most mobile. Land is
perfectly immobile. Labour and entrepreneur also lack mobility. Capital
can be easily transported from one place to another.