Which of the following statements is correct regarding the slant or horizontal demand elasticity between two goods?
1
When the two goods are perfect substitutes, the horizontal demand elasticity is zero.
2
When two goods are completely independent of each other, the horizontal elasticity of demand is infinite.
3
When two goods are complementary, the horizontal elasticity of demand is positive.
4
When two goods are jointly demanded, the horizontal elasticity of demand is negative.