Why was the steel-faced plow an important invention?

In the image, layer a is the topmost layer. layer c contains fossils from the precambrian era. layer b contains dinosaur fossils, and layer a contains fossils of mammals. which two statements are supported by this evidence? 1. mammals lived before the precambrian era. 2. dinosaurs and mammals existed in the precambrian era. 3. dinosaurs evolved after precambrian organisms. 4. precambrian organisms evolved after dinosaurs. 5. precambrian organisms were the first life-forms to become fossilized, according to this sample.

Panthers and leopards prey on deer in an ecosystem. for unknown reasons, the population of leopards increased drastically. what are the likely effects of this change on the species? 1. more food for panthers and more competition for leopards 2. less food and more competition for panthers 3. fewer deer and more competition for panthers 4. more food for deer and less competition for panthers and leopards 5. more food for leopards and less competition for panthers

What is the highest grade you can score on the act