If the price of food falls by 10 percent and the quantity sold increases by 5 percent, then the price elasticity of demand in that range equals

If demand is price inelastic,

Average fixed cost is

Positive economics deals with

The elasticity of supply is calculated by

Signals

Crying is a way to communicate.

Physical contact helps create strong emotional bonds.

What treatable condition in the mother often follows a baby’s birth?

The sensorimotor period includes understanding the idea of ___________________ permanence.