In which step of the engineering design process do you make a plan, decide what materials you will use, and decide which steps you will take?

Preliminary design stage

Explanation:

During preliminary design stage, the engineers and other stakeholders involved in a project are tasked to carry out a detailed design and also give proposed methodology that would be used to achieve the desired results. Thereafter, when the design is approved, the design review follows as it is being implemented. The importance of having design review is that some site conditions may change and such aspects may not have been considered during preliminary design stage.