1. Which method is used to stack layers in a Keras Sequential model?
2. What is a mandatory argument while compiling a Keras model?
3. How do you save the entire model (architecture, weights, and training configuration) in Keras?
4. What is the purpose of the `EarlyStopping` callback in Keras?
5. What is the purpose of using Keras Tuner?
6. Why is data normalization important before training a Keras model?
7. How does the batch size affect model training in Keras?
8. In Keras, why is feature scaling important for neural network training?