7886
Most of the design constraints of small-scale polymer 3D printers still apply to BAAM .
 engineering feature: design; material: polymer; machine or equipment: 3D printers
Given options, please tell me the categories of all the listed entity words.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} 
 Entities: design, polymer, 3D printers 
Answer:
 engineering feature: design; material: polymer; machine or equipment: 3D printers