Physics MCAT content review

1) When a doctor injects someone with a hypodermic needle, she exerts about 15 N of force to pierce adult skin. Once the skin has been pierced considerably less force is required to push the needle deeper. If a force of 5N on the plunger is required to initiate the injection, how hard should one pull back on the barrel to minimize risk of hematoma to the patient once the needle is inserted into the vein?

I do not understand the question in this.

2) Newtons Second Law states that an object will accelerate in the direction Fnet feels but will not always move in the direction of Fnet.