Ethics are principles that govern a person’s behavior or the conducting of an activity
You can draw a free body diagram with two 250N forces acting on the human, one from each side. The net force is 0 because the two applied forces cancel each other out since they are in opposite directions.
Answer:Valves stop blood flowing backwards
Explanation: Valve are flags of tissue that control the direction of the blood in our heart.,it prevent the backwards flow of blood. valves regulate blood from flowing back into the atria.The right and left atrio-ventricular valves prevent blood from flowing backwards into atria. When the ventricle is full,the valve prevent backwards flow of blood.
C) change of a caterpillar into an adult butterfly.
