Final answer:
The part of the hypodermic needle that connects to the syringe is called the hub, and the topic is related to biology or medicine.
Step-by-step explanation:
The portion of a hypodermic needle that attaches to the syringe is termed its hub. The question provided seems to involve a calculation related to the flow rate and velocity of liquid through a syringe, which are principles typically applied in physics or engineering.
However, to give a complete solution, one would need to calculate the area of both the barrel and the needle and then use these to determine the flow rates and velocity. Since the full question does not appear to be provided, I can only address the part about the anatomy of the needle, which is primarily a topic in biology or medicine.