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Solution

In Iterative Enhancement Model, the complete system is not developed at once.

The requirements are divided into parts or categories.

Then each category of requirements is implemented step by step in different iterations.

After every iteration, the software is improved by adding new features or enhancing existing features.

Waterfall model follows a fixed sequence of phases.

Prototyping model focuses on making a prototype first.

Evolutionary model evolves the software with user feedback.

But implementing requirements category-wise is mainly related to Iterative Enhancement Model.