Okay so, you didn't include a screen shot or anything of what the text is, so I tried my best to answer your question without it.
There may be no land at the North Pole due to the fact that it could just all be ice that's floating atop the Arctic Ocean. Over the past few decades, scientists have discovered that the ice is thinning, therefore the likeliness of land beneath it is not great.
The answer is: factual.
Tone is the attitude or feeling of the author as regards the topic or subject of a piece of writing. The excerpt has a factual tone because it is concerned with the actual, genuine reality rather than perceptions or reactions towards it.
The tone is not emotional because it does not relate to anybody's emotions. Mysterious is not correct either since the events are not difficult to understand or explain. Finally, the tone is not critical for the reason that the text does not express disapproval or objection.
Answer:
Optimization often requires making trade-offs among competing criteria. When multiple possible design options are under consideration, with each optimized for different criteria, engineers may use a trade-off matrix to compare the overall advantages and disadvantages of the different proposed solutions.
Explanation:
What is the question here