Answer:
Explanation:
When we pull the piston from inside to outside a suction is created between the liquid and the piston. This causes the liquid to move upwards and this allows us to draw a drug from a bottle
B A syringe is just a hollow tube with a plunger at one end. After the needle is inserted into the vein (usually), the plunger is moved distally from the needle end, (pull the plunger back), and a negative air space is created that has less pressure that the vein
