Question

1. The ______________ Boundary is the turning point in earth's history, when dinosaurs vanished.

Answer 1

The K-T extinction

Step-by-step explanation:

This extinction event marks a major boundary in Earth's history, the K-T or Cretaceous-Tertiary boundary, and the end of the Mesozoic Era. The K-T extinctions were worldwide, affecting all the major continents and oceans.