1. MATCHING: Match the correct geological era with the items listed below. Choices will be used more than once. 1. The first one-celled organisms (microscopic life) appear a. Mesozoic Era b. Precambrian Era 2. Age of the oldest rocks c. Cenozoic Era 3. The "Age of Reptiles" d. Paleozoic Era 4. This era lasted nearly 4 billion years 5. This era started 248 million years ago 6. Dinosaurs became extinct 7. The "Age of Mammals" 8. The first land animals appear