the difference in altitude represented by the space between two contour lines on a map. At least i think youre looking for the definition. And if you are hope this helps :)
These are some ways how scientists and engineers develop, use and refine models.
1. Imagine. They have to know what exactly trying to model. They have to imagine and brainstorm what are the things to be considered.
2. Reason. Next, they need to answer the questions brought from their brainstorming. They need to be able to reason out.
3. Calculate and Predict. Once they know it, that's the time they can start modelling and calculate - and predict.
Answer:
what are you trying to ask about?
Dinosaurs became common on land
Their father is the correct answer
