2078
Thomas investigated the quality of produced channels and found that round holes up to a diameter of 7mm could be printed with minimal problems .
 concept or principle: quality; concept or principle: diameter; material: be
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: manufacturing standard, machanical property, manufacturing process, material, engineering feature, process parameter, machine or equipment, application, process characterization, enabling technology, biomedical, concept or principle 
Text: {0} 
Answer:
 concept or principle: quality; concept or principle: diameter; material: be