Do you understand the necessity of this project?

That information is unnecessary.

That information is completely unnecessary.

A new approach is needed to solve this set of problems.

The main problem with this project is the lack of communication.

This question text is too difficult, it's hard to understand.

This exam is a matter of life or death for me.

He is viewing that situation as a serious problem.

He views that situation as a problem.

No problem, I will do that job.