Answer:
The line which supports the idea that Dean's time at Worcester Polytechnic Institute was very useful even if he did not graduate is:
I found that at college I could get help from my teachers with solving business problems and in learning new techniques for designing new things.
Step-by-step explanation:
"I found that at college I could get help from my teachers with solving business problems and in learning new techniques for designing new things."
According to the line above, Dean learned a lot from teachers. They helped him and offered him the knowledge he needed. We know he did not graduate, but it is clear that those teachers had an impact in what he was able to do as an inventor. After all, they did help him with "solving business problems and in learning new techniques for designing new things." Therefore, his time at the Institute was still useful due to the knowledge and help he received.