Suppose a packaging inspector decides to inspect a sample from a crate of eggs for freshness. each crate has 5 trays of 30 eggs each stacked on top of each other. the inspector decides to examine only

Suppose a packaging inspector decides to inspect a sample from a crate of eggs for freshness. each crate has 5 trays of 30 eggs each stacked on top of each other. the inspector decides to examine only the top row. why is this sample biased?