it isn't that hard to answer your question, but there are a few tricky concepts that can take some time and practice to get used to.
The content is focused on:
- mechanics
- materials
- electronics
- drawing
- historical and societal and scope of profession stuff
it can be considered hard in the fact that there is a lot of content and such a diverse range of skills and questions that can be asked. imo its like a mix of math, physics, chem sorta, art, and just history and materials and other stuff. So it can be overwhelming at times.